# Make It Stick (Digest)

This is a digest of the book Make it stick. I'm assuming that uploading the digest alone should be alright. If I were wrong, please let me know (http://bigaidream.github.io/contact.html) as soon as possible, and I will delete it immediately.

## Ch1, Make It Stick, the Science of Successful Learning (Digest)

### Learning is Misunderstood

Claims We Make in This Book

• Learning is deeper and more durable when it's effortful.
• we are poor judges of when we are learning well and when we're not. When the going is harder and slower and it doesn't feel productive, we are drawn to strategies that feel more fruitful, unaware that the gains from these strategies are often temporary.
• Rereading text and massed practice of a skill or new knowledge are by far the preferred study strategies of learners of all stripes, but they're also among the least productive.
• Retrieval practice --recalling facts or concepts or events from memory--is a more effective learning strategy than review by rereading. Flashcards are a simple example. A single, simple quiz after reading a text or hearing a lecture produces better learning and remembering than rereading the text or reviewing lecture notes. Periodic practice arrests forgetting, strengthens retrieval routes, and is essential for hanging onto the knowledge you want to gain.
• When you space out practice at a task and get a little rusty between sessions, or you interleave the practice of two or more subjects, retrieval is harder and feels less productive, but the effort produces longer lasting learning and enables more versatile application of it in later settings.
• Trying to solve a problem before being taught the solution leads to better learning, even when errors are made in the attempt.
• When you'are adept at extracting the underlying principles or "rules" that differentiate types of problems, you're more successful at picking the right solutions in unfamiliar situations. This skill is better acquired through interleaved and varied practice than massed practice.
• Testing helps calibrate our judgments of what we've learned.
• All new learning requires a foundation of prior knowledge.
• If you are just engaging in mechanical repetition, you quickly hit the limit of what you can keep in mind. However, if you practice elaboration, there's no known limit to how much you can learn. Elaboration is the process of giving new material meaning by expressing it in your own words and connecting it with what you already know. The more you can explain about the way your new learning relates to your prior knowledge, the stronger your grasp of the new learning will be, and the more connections you create that will help you remember it later.
• Putting new knowledge into a larger context helps learning.
• People who learn to extract the key ideas from new material and organize them into a mental model and connect the model to prior knowledge show an advantage in learning complex mastery.
• Many people believe that their intellectual ability is hardwired from birth, and that failure to meet a learning challenge is an indictment of their native ability. But every time you learn something new, you change the brain --the residue of your experiences is stored.

### Illusions of Knowing

If rereading is largely ineffective, why do students favor it? Rising familiarity with a text and fluency in reading it can create an illusion of mastery.

## Ch2, To Learn, Retrieve

### Reflection Is a Form of Practice

Reflection can involve several cognitive activities that lead to stronger learning: retrieving knowledge and earlier training from memory, connecting these to new experiences, and visualizing and mentally rehearsing what you might do differently next time.

### The Testing Effect

Practicing retrieval makes learning stick far better than re-exposure to the original material does. This is the testing effect, also known as the retrieval-practice effect.

### Studying the Testing Effect in the Lab

When retrieval practice is spaced, allowing some forgetting to occur between tests, it leads to stronger long-term retention than when it is massed.

### The Takeaway

Practice at retrieving new knowledge or skill from memory is a potent tool for learning and durable retention. Effortful retrieval makes for stronger learning and retention. The greater the effort to retrieve learning, provided that you succeed, the more that learning is strengthened by retrieval. After an initial test, delaying subsequent retrieval practice is more potent for reinforcing retention than immediate practice, because delayed retrieval requires more effort. Repeated retrieval not only makes memories more durable but produces knowledge that can be retrieved more readily, in more varied settings, and applied to a wider variety of problems. While cramming can produce better scores on an immediate exam, the advantage quickly fades because there is much greater forgetting after retreading than after retrieval practice. The benefits of retrieval practice are long-term. Simply including one test (retrieval practice) in a class yields a large improvement in final exam scores, and gains continue to increase as the frequency of classroom testing increases. Testing doesn't need to be initiated by the instructor. Students can practice retrieval anywhere; no quizzes in the classroom are necessary. Think flashcards -- the way second graders learn the multiplication tables can work just as well for learners at any age to quiz themselves on anatomy, mathematics, or law. Self-testing may be unappealing because it takes more effort than rereading, but as noted already, the greater the effort at retrieval, the more will be retained. Students who take practice testes have a better grasp of their progress than those who simply reread the material. Giving students corrective feedback after tests keeps them from incorrectly retaining material they have misunderstood and produces better learning of the correct answers.

## Ch3, Mix Up Your Practice

### The Myth of Massed Practice

If learning can be defined as picking up new knowledge or skills and being able to apply them later, then how quickly you pick something up is only part of the story. Is it still there when you need to use it out in the everyday world?

Practice is far more effective when it's broken into separate periods of training that are spaced out. Practice that's spaced out, interleaved with other learning, and varied produces better mastery, longer retention, and more versatility. But these benefits come at a price: when practice is spaced, interleaved, and varied, it requires more effort.

### Spaced Practice

Why is spaced practice more effective than massed practice? It appears that embedding new learning in long-term memory requires a process of consolidation, in which memory traces (the brain's representations of the new learning) are strengthened, given meaning, and connected to prior knowledge - a process that unfolds over hours and may take several days.

### Interleaved Practice

Interleaving the practice of two or more subjects or skills is also a more potent alternative to massed practice, and here's a quick example of that. Two groups of college students were taught how to find the volumes of four obscure geometric solids (wedge, spheroid, spherical cone, and half cone). One group then worked a set of practice problems that were clustered by problem type (practice four problems for computing the volume of a wedge, then four problems for a spheroid, etc.). The other group worked the same practice problems, but the sequence was mixed (interleaved) rather than clustered by type of problem. During practice, the students who worked the problems in clusters (that is, massed) averaged 89 percent correct, compared to only 60 percent for those who worked the problems in a mixed sequence. But in the final test a week later, the students who had practiced solving problems clustered by type averaged only 20 percent correct, while the students whose practice was interleaved averaged 63 percent.

Now, suppose you 're a trainer in a company trying to teach employees a complicated new process that involves ten procedures. They typical way of doing this is to train up in procedure 1, repreating it many times until the trainess really seem to have it down cold. Then you go to procedure 2, you do many repetitions of 2, you get that down, and so on. That appears to produce fast learning. What would interleaved practice look like? You practice procedure 1 just a few times, then switch to procedure 4, then switch to 3, then to 7, and so on.

Research shows unequivocally that mastery and long-term retention are much better if you interleave practice than if you mass it.

### Developing Discrimination Skills

Compared to massed practice, a significant advantage of interleaving and variation is that they help us learn better how to assess context and discriminate between problems, selecting and applying the correct solution from a range of possibilities.

### The Takeaway

The simple act of spacing out study and practice in installments and allowing time to elapse between them makes both the learning and the memory stronger, in effect building habit strength. How big an interval, you ask? The simple answer: enough so that practice doesn't become a mindless repetition. At a minimum, enough time so that a little forgetting has set in. A little forgetting between practice sessions can be a good thing, if it leads to more effort in practice, but you do not want so much forgetting that retrieval essentially involves relearning the material. The time periods between sessions of practice let memories consolidate.

Something as simple as a deck of flashcards can provide an example of spacing.

Beware of the familiarity trap: the feeling that you know something and no longer need to practice it. The familiarity can hurt you during self-quizzing if you take shortcuts. You have to be disciplined to say, "All right, I'm going to make myself recall all of this and if I don't, what did I miss, how did I not know that?"

Interleaving two or more subjects during practice also provides a form of spacing. Interleaving can also help you develop your ability to discriminate later between different kinds of problems and select the right tool from your growing toolkit of solutions.

In interleaving, you don't move from a complete practice set of one topic to go to another. You switch before each practice is complete .A friend of ours describes his own experience with this: "I go to a hockey class and we're learning skating skills, puck handling, shooting, and I notice that I get frustrated because we do a little bit of skating and just when I think I'm getting it, we go to stick handling, and I go home frustrated, saying, 'Why doesn't this guy keep letting us do these things until we get it?' " This is actually the rare coach who understands that it's more effective to distribute practice across these different skills than polish each one in turn.

Like interleaving, varied practice helps learners build a broad schema, an ability to asses changing conditions and adjust responses to fit. Arguably, interleaving and variation help learners reach beyond memorization to higher levels of conceptual learning and application, building more rounded, deep, and durable learning, what in motor skills shows up as underlying habit strength.

## Ch4, Embrace Difficulties

### How Learning Occurs

• Encoding
• Consolidation
• Retrieval Durable, robust learning requires that we do two things. First, as we recode and consolidate new material from short-term memory into long-term memory, we must anchor it here securely. Second, we must associate the material with a diverse set of cues that will make us adept at recalling the knowledge later.

### Extending Learning: Updating Retrieval Cues

Knowledge is more durable if it's deeply entrenched, meaning that you have firmly and thoroughly comprehended a concept, it has practical importance or keen emotional weight in your life, and it is connected with other knowledge that you hold in memory. The parodox is that some forgetting is often essential for new learning.

### Easier Isn't Better

The easier knowledge or a skill is for you to retrieve, the less your retrieval practice will benefit your retention of it. Conversely, the more effort you have to expend to retrieve knowledge or skill, the more the practice of retrieval will entrench it.

### How Effort Helps

#### Reconsolidating Memory

Effortful recall of learning, as happens in spaced practice, requires that you reload or reconstruct the components of the skill or material anew from long-term memory rather than mindlessly repeating them from short-term memory.

The more effort that is required to recall a memory or to execute a skill, provided that the effort succeeds, the more the act of recalling or executing benefits the learning.

Massed practice gives us the warm sensation of mastery because we're looping information through short-term memory without having to reconstruct the learning from long-term memory.

#### Creating Mental Models

Retrieval practice that you perform at different times and in different contexts and that interleaves different learning material has the benefit of linking new associations to the material.

#### Fostering Conceptual Learning

The difficulty produced by interleaving provides a second type of boost to learning. Interleaved practice of related but dissimilar geometric solids requires that you notice similarities and differences in order to select the correct formula for computing the volume.

#### Improving Versatility

The retrieval difficulties posed by spacing, interleaving, and variation are overcome by invoking the same mental processes that will be needed later in applying the learning in everyday settings. By mimicking the challenges of practical experience, these learning strategies conform to the admonition to "practice like you play, and you'll play like you practice," improving what scientists call transfer of learning, which is the ability to apply what you've learned in new settings.

#### Priming the Mind for Learning

When you're asked to struggle with solving a problem before being shown how to solve it, the subsequent solution is better learned and more surably remembered.

### Other Learning Strategies That Incorporate Desirable Difficulties

We usually think of interference as a detriment to learning, but certain kinds of interference can produce learning benefits, and the positive effects are sometimes surprising.

When letters are omitted from words in a text, requiring the reader to supply them, reading is slowed, and retention improves. The added effort increases comprehension and learning. (Of course, learning will not improve if the difficulty completely obscures the meaning or cannot be overcome.)

When you're asked to supply an answer or a solution to something that's new to you, the power of generation to aid learning is even more evident. One explanation for this effect is the idea that as you cast about for a solution, retrieving related knowledge from memory, you strengthen the route to a gap in your learning even before the answer is provided to fill it and, when you do fill it, connections are made to the related material that is fresh in your mind from the effort. It's better to solve a problem than to memorize a solution. It's better to attempt a solution and supply the incorrect answer than not to make the attempt.

The act of taking a few minutes to review what has been learned from an experience (or in a recent class) and asking yourself questions is know as reflection. After a lecture or reading assignment, for example, you might ask yourself: What are the key ideas? What are some examples? How do these relate to what I already know?

One form of reflection that is gaining currency in classroom settings is called "write to learn." In essence, students reflect on a recent class topic in a brief writing assignment, where they may express the main ideas in their own words and relate them to other concepts covered in class, or perhaps outside class.

### Failure and the Myth of Errorless Learning

People who are taught that learning is a struggle that often involves making errors will go on to exhibit a greater propensity to tackle tough challenges and will tend to see mistakes not as failures but as lessons and turning points along the path to mastery.

Studies underscore the importance of learners understanding that difficulty in learning new things is not only to be expected but can be beneficial. It's trusting that trying to solve a puzzle serves us better than being spoon-fed the solution, even if we fall short in our first attempts at an answer.

### Undesirable Difficulties

Desirable difficulties are desirable because they trigger encoding and retrieval processes that support learning, comprehension, and remembering. If, however, the learners does not have the background knowledge or skills to respond to them successfully, they become undesirable difficulties.

### The Takeaway

Learning is at least a three-step process:

1. Initial encoding of information is held in short-term working memory before being consolidated into a cohesive representation of knowledge in long-term memory.
2. Consolidation reorganizes and stabilizes memory traces, gives them meaning, and makes connections to past experiences and to other knowledge already stored in long-term memory.
3. Retrieval updates learning and enables you to apply it when you need it.

Learning always builds on a store of prior knowledge. We interpret and remember events by building connections to what we already know.

Long-term memory capacity is virtually limitless: the more you know, the more possible connections you have for adding new knowledge.

Periodic retrieval of learning helps strengthen connections to the memory and the cues for recalling it, while also weakening routes to competing memories. Retrieval practice that's easy does little to strengthen learning; the more difficult the practice, the greater the benefit.

When you recall learning from short-term memory, as in rapid-fire practice, little mental effort is required, and little long-term benefit accrues. But when you recall it after some time has elapsed and your grasp of it has become a little rusty, you have to make an effort to reconstruct it. This effortful retrieval both strengthens the memory but also makes the learning pliable again, leading to its reconsolidation.

Reconsolidation helps update your memories with new information and connect them to more recent learning.

Repeated effortful recall or practice helps integrate learning into mental models, in which a set of interrelated ideas or a sequence of motor skills are fused into a meaningful whole that can be adapted and applied in later settings. When practice conditions are varied or retrieval is interleaved with the practice of other material, we increase our abilities of discrimination and induction and the versatility with which we can apply the learning in new settings at a later date. Interleaving and variation build new connections, expanding and more firmly entrenching knowledge in memory and increasing the number of cues for retrieval.

Trying to come up with an answer rather than having it presented to you, or trying to solve a problem before being shown the solution, leads to better learning and longer retention of the correct answer or solution, even when your attempted response is wrong, so long as corrective feedback is provided.

## Ch5, Avoid Illusions of Knowing

At the root of our effectiveness is our ability to grasp the world around us and to take the measure of our own performance.

### Two Systems of Knowing

1. System 1: (or the automatic system) is unconscious, intuitive, and immediate.
2. System 2 (the controlled system) is our slower process of conscious analysis and reasoning.

### Illusions and Memory Distortions

Accounts that sound familiar can create the feeling of knowing and be mistaken for true.

Fluency illusions result from our tendency to mistake fluency with a text for mastery of its content. Students who study by rereading their texts can mistake their fluency with a text, gained from rereading, for possession of accessible knowledge of the subject and consequently overestimate how well they will do on a test.

### Unskilled and Unaware of It

Incompetent people overestimate their own competence and, failing to sense a mismatch between their performance and what is desirable, see no need to try to improve.

### Tools and Habits for Calibrating Your Judgment

Most important is to make frequent use of testing and retrieval practice to verify what you really do know versus what you think you know.

## Ch6, Go Beyond Learning Styles

We acknowledge that everyone has learning preferences, but we are not persuaded that you learn better when the manner of instruction fits those preferences. Yet there are other kinds of differences in how people learn that do matter.

### Active Learning from the Get-Go

One difference that appears to matter a lot is how you see yourself and your abilities. Whether you think you can or you think you cannot, you 're right. Each of us has a large basket of resources in the form of aptitudes, prior knowledge, intelligence, interests, and sense of personal empowerment that shape how we learn and how we overcome our shortcomings. Some of these differences matter a lot - for example, our ability to abstract underlying principles from new experiences and to convert new knowledge into mental structures. Other differences we may think count for a lot, for example having a verbal or visual learning style, actually don't.

### Dynamic Testing

A test may assess a weakness, but rather than assuming that the weakness indicates a fixed inability, you interpret it as a lack of skill or knowledge that can be remedied. What do I need to learn in order to improve? Dynamic testing has three steps:

1. A test of some kind - perhaps an experience or a paper exam - shows me where I come up short in knowledge or a skill.
2. I dedicate myself to becoming more competent, using reflection, practice, spacing, and the other techniques of effective learning.
3. I test myself again, paying attention to what works better now but also, and especially, to where I still need more work.

### Structure Building

There do appear to be cognitive differences in how we learn, though not the ones recommended by advocates of learning styles. One of these differences is the idea mentioned earlier that psychologists call structure building: the act, as we encounter new material, of extracting the salient ideas and constructing a coherent mental framework out of them. These frameworks are sometimes called mental models or mental maps. High structure-builders learn new material better than low structure-builders. The theory of structure building bears some resemblance to a village built of Lego blocks. We know that when questions are embedded in texts to help focus readers on the main ideas, the learning performance of low structure-builders improves to a level commensurate with high structure-builders.

### Rule versus Example Learning

We know that high structure-builders and rule learners are more successful in transferring their learning to unfamiliar situations than are low structure-builders and example learners.

### The Takeaway

Be the one in charge There's an old truism from sales school that says you can't shoot a deer from the lodge. The same goes for learning: you have to suit up, get out the door, and find what you're after. Mastery, especially of complex ideas, skills, and processes, is a quest. It is not a grade on a test, something bestowed by a coach, or a quality that simply seeps into your being with old age and gray hair.

Embrace the notion of successful intelligence Go Wide: don't roost in a pigeonhole of your preferred learning style but take command of your resources and tap all of your "intelligences" to master the knowledge or skill you want to possess. Describe what you want to know, do, or accomplish. Then list the competencies required, what you need to learn, and where you can find the knowledge or skill. Then go get it. Consider your expertise to be in a state of continuing development, practice dynamic testing as a learning strategy to discover your weaknesses, and focus on improving yourself in those areas. It's smart to build on your strengths, but you will become ever more competent and versatile if you also use testing and trial and error to continue to improve in the areas where your knowldege or performance are not pulling their weight.

Adopt active learning strategies like retrieval practice, spacing, and interleaving. Be aggressive.

Don't rely on what feels best: like a good pilot checking his instruments, use quizzing, peer review, and the other tools described AVOID ILLUSIONS OF KNOWING to make sure your judgment of what you know and can do is accurate, and that your strategies are moving you toward your goals. Don't assume that you're doing something wrong if the learning feels hard. Remember that difficulties you can overcome with grater cognitive effort will more than repay you in the depth and durability of your learning.

Distill the underlying principles; build the structure If you're an example learner, study examples two at a time or more, rather than one by one, asking yourself in what ways they are alike and different. Are the differences such that they require different solutions, or are the similarities such that they respond to a common solution?

Break your idea or desired competency down into its component parts. If you think you are a low structure-builder or an example learner trying to learn new material, pause periodically and ask what the central ideas are, what the rules are. Describe each idea and recall the related points. Which are the big ideas, and which are supporting concepts or nuances? If you were to test yourself on the main ideas, how would you describe them?

Structure is all around us and available to us through the poet's medium of metaphor. A tree, with its roots, trunk, and branches.

By abstracting the underlying rules and piecing them into a structure, you go for more than knowledge. You go for know-how. And that kind of mastery will put you ahead.

### Is IQ Mutable?

Gains in IQ were found in several areas of cognitive training.

### Brain Training

Since it's unlikely I'll be raising my IQ anytime soon, are there strategies or behaviors that can serve as cognitive "multipliers" to amp up the performance of the intelligence I've already got? Yes. Here are three: embracing a growth mindset, practicing like an expert, and constructing memory cues.

### Growth Mindset

Attitude counts for a lot. More than IQ, it's discipline, grit, and a growth mindset that imbue a person with the sense of possibility and the creativity and persistence needed for higher learning and success.

### Deliberate Practice

Deliberate practice is goal directed, often solitary, and consists of repeated striving to reach beyond your current level of performance. Whatever the field, expert performance is thought to be garnered through the slow acquisition of a larger number of increasingly complex patterns, patterns that are used to store knowledge about which actions to take in a vast vocabulary of different situations.

The central idea here is that expert performance is a product of the quantity and the quality of practice, not of genetic predisposition, and that becoming expert is not beyond the reach of normally gifted people who have the motivation, time, and discipline to pursue it.

### Memory cues

Image cue memories. With continued retrieval, complex material can become second nature to a person and the mnemonic cues are no longer needed: you consolidate concepts like Newton's 3 laws of motion into mental models that you use as a kind of short-hand. Through repeated use, your brain encodes and "chunks" sequences of motor and cognitive actions, and your ability to recall and apply them becomes as automatic as habit.

### The Takeaway

Effortful learning changes the brain, building new connections and capability. This single fact - that our intellectual abilities are not fixed from birth but are, to a considerable degree, outs to shape - is a resounding answer to the nagging voice that too often asks us "Why bother?" We make the effort because the effort itself extends the boundaries of our abilities. What we do shapes who we become and what we're capable of doing. The more we do, the more we can do. To embrace this principle and reap its benefits is to be sustained through life by a growth mindset.

And it comes down to the simple fact that the path to complex master or expert performance does not necessarily start from exceptional genes, but it most certainly entails self-discipline, grit, and persistence; with these qualities in healthy measure, if you want to become an expert, you probably can. And whatever you are striving to master, whether it's a poem you wrote for a friend's birthday, the concept of classical conditioning in psychology, conscious mnemonic devices can help to organize and cue the learning for ready retrieval until sustained, deliberate practice and repeated use form the deeper encoding and subconscious mastery that characterize expert performance.

## Ch8, Make It Stick

### Learning Tips for Students

Embrace the fact that significant learning is often, or even usually, somewhat difficult. You will experience setbacks. These are signs of effort, not of failure. Setbacks come with striving, and striving builds expertise. Effortful learning changes your brain, making new connections, building mental models. increasing your capability. Your intellectual abilities lie to a large degree within your own control. Knowing that this is so makes the difficulties worth tackling. Following are three keystone study strategies. Make a habit of them and structure your time so as to pursue them with regularity.

#### Practice Retrieving New Learning from Memory

"Retrieval practice" means self-quizzing. Retrieving knowledge and skill from memory should become your primary study strategy in place of rereading.

How to use retrieval practice as a study strategy: When you read a text or study lecture notes, pause periodically to ask yourself questions like these, without looking in the text: What are the key ideas? What terms or ideas are new to me? How would I define them? How do the ideas relate to what I already know?

Many textbooks have study questions at the ends of the chapters, and these are good fodder for self-quizzing. Generating questions for yourself and writing down the answers is also a good way to study.

Set aside a little time every week throughout the semester to quiz yourself on the material in a course, both the current week's work and material covered in prior weeks. When you quiz yourself, check your answers to make sure that your judgments of what you know and don't know are accurate.

Use quizzing to identify areas of weak mastery, and focus your studying to make them strong.

The harder ti is for you to recall new learning from memory, the greater the benefit of doing so. Making errors will not set you back, so long as you check your answers and correct your mistakes.

#### Space Out Your Retrieval Practice

What does this mean: Spaced practice means studying information more than once but leaving considerable time between practice sessions. How to use spaced practice as a study strategy: Establish a schedule of self-quizzing that allows time to elapse between study sessions. How much time? It depends on the material. If you are learning a set of names and faces, you will need to review them within a few minutes of your first encounter, because these associations are forgotten quickly. New material in a text may need to be revisited within a day or so of your first encounter with it. Then, perhaps not again for several days or a week. When you are feeling more sure of your mastery of certain material, quiz yourself on it once a month. Over the course of a semester, as you quiz yourself on new material, also reach back to retrieve prior material and ask yourself how that knowledge relates to what you have subsequently learned. Anything you want to remember must be periodically recalled from memory.

Another way of spacing retrieval practice is to interleave the study of two or more topics, so that alternating between them requires that you continually refresh your mind on each topic as you return to it.

What your intuition tells you to do: Intuition persuades us to dedicate stretches of time to single-minded, repetitive practice of something we want to master, the massed "practice-practice-practice" regime we have been led to believe is essential for building mastery of a skill or learning new knowledge. These intuitions are compelling and hard to distrust for two reasons. First, as we practice a thing over and over we often see our performance improving, which serves as a powerful reinforcement of this strategy. Second, we fail to see that the gains made during single-minded repetitive practice come from short-term memory and quickly fade. Our failure to perceive how quickly the gains fade leaves us with the impression that massed practice is productive.

Why spaced practice is better: It's a common but mistaken belief that you can burn something into memory through sheer repetition. Lots of practice works, but only if it's spaced.

If you use self-quizzing as your primary study strategy and space out your study sessions so that a little forgetting has happened since your last practice, you will have to work harder to reconstruct what you already studied. If effect, you're "re-loading" it from long-term memory. This effort to reconstruct the learning makes the important ideas more salient and memorable and connects them more securely to other knowledge and to more recent learning.

How it feels: Massed practice feels more productive than spaced practice, but it is not. Spaced practice feels more difficult, because you have gotten a little rusty and the material is harder to recall. It feels like you're not really getting on top of it,

#### Interleave the Study of Different Problem Types

What does this mean? If you're trying to learn mathematical formulas, study more than one type at a time, so that you are alternating between different problems that call for different solutions. If you are studying biology specimens, Dutch painters, or the principles of macroeconomics, mix up the examples. How to use interleaved practice as a study strategy: Many textbooks are structured in study blocks: THey present the solution to a particular kind of problem, say, computing the volume of a spheroid, and supply many examples to solve before moving to another kind of problem (computing the volume of a cone). Blocked practice is not as effective as interleaved practice, so here's what to do. When you structure your study regimen, once you reach the point where you understand a new problem type and its solution but your grasp of it is still rudimentary, scatter this problem type throughout your practice sequence so that you are alternately quizzing yourself on various problem types and retrieving the appropriate solutions for each. If you find yourself falling into single-minded, repetitive practice of a particular topic or skill, change it up: mix in the practice of other subjects, other skills, constantly challenging your ability to recognize the problem type and select the right solution. What your intuition tells you to do: Most learners focus on many examples of one problem or specimen type at a time, wanting to master the type and "get it down cold" before moving on to study another type. Why interleaved practice is better: Mixing up problem types improves your ability to discriminate between types, identify the unifying characteristics within a type, and improves your success in a later test where you must discern the kind of problem you're trying to solve in order to apply the correct solution.