Interleaving

How It Works

    Step 1: Gather and Assess

    Step 2: Divide and Conquer

    Step 3: Study Session 1!

    Step 4: Study Session 2!

    Step 5: Any Future Study Sessions

Why It Works

    Break It Until You Make It

    Novelty

    Primacy and Recency

    Historical Thinking ​

Interleaving is a scientifically-backed, effective way to study large amounts of information.  To use interleaving, we will break down large units into smaller sections.  Then, we vary the order that we study the information in.  ​

The first thing to do is to gather all of the materials you have from your class that are relevant to this particular exam.  Ideally, you're already storing everything in the same place.  In practice, life is not always ideal.  You may have some assignments stored in a Google Drive, some paper notes in a notebook, and some handouts that are living with your science materials.  No judgement!  Just go gather everything into one spot.

Once you've gathered everything up, survey the situation.  Look for any materials that you're confident that you don't have to review.  If this test won't have a Document Based Question, you can set aside your teacher's feedback on a previous essay.  If the quiz only covers the first half of the unit, then you don't need anything from the second half.  You also don't need anything from previous units in that situation.

Taking stock of the situation before you start often reduces the amount of things you're sifting through while trying to study.  This can cut down on the overwhelm, and it's easier to fewer things better.  We don't want to waste our valuable time with things that won't move the needle very much. ​

Next, take the content you'd like to study and break it down into smaller pieces.  Ideally, each piece will be something you can tackle in about 20 minutes of focused review.

Here are some pieces that work well for AP history courses:

Once you have your groups, you'll label each one with a letter.

For example, let's say that I'm working with notes from my textbook.  I have taken notes on five chapters of the textbook.  I would label my Chapter 12 notes with the letter "A."  Chapter 13 becomes "B."  Chapter 14 is "C."  I would continue that process until each of my five chapters was labeled with a letter between A and E. ​

Start by memorizing the information in the first group (Group A).  I recommend spending about 20 minutes on this step, but you can experiment with the time to find what works with you.  It's important to set relatively small time increments here.  You've got multiple groups to study, so you need to allow time to complete all of the sets.

If you need some tips for what to do during this time, any of the following are great options:

• Blurting Method
• Flashcard Practice (not flashcard creation)
• Elaboration and Reflection

So far, this is all fairly standard studying.  But this is where interleaving gets all of it's power.

During the second study session, we're going to work with the same material we had last time.  But this time, we're going to study the material in a different order.  Instead of studying in alphabetical order, we'll scramble up the choices.  The specific new order doesn't matter.  We just want to see the material in a new way.  This step should be quick and easy!  Don't overthink it!

Here are some potential options:

Now, you've got all the steps in the process!  For any additional study sessions, simply randomize the topics into a new order.  Repeat until exam day! ​

The easiest way to tame an overwhelming task is to break it into smaller pieces.  Then, tackle each of the pieces in turn.  Interleaving gives you a structured way to break down tasks and then study them.

This has two major benefits.

First, it's easier to start a smaller task.  Smaller tasks tend to be more clearly defined and manageable.  "Study all of Unit Six" is really big and vague.  What does studying look like?  Is it flashcards, notes, the textbook, or something else?  How will you know when you've completed "all" of Unit Six?  Does that mean you've looked it over?  Does that mean you can explain it?  Does that mean you can remember it?

Interleaving forces you to grapple with these questions before you start studying.  This helps you gain clarity about your task, which is motivating.

Second, motivation for a task often shows up after you start.  Therefore, if we can make it easier to start, then often the motivation to finish the task kicks in.  Motivation doesn't show up through willpower.  You can't make yourself want to do something.  But often, you can make yourself do one small step in the process.  That sets you up to finish a larger project.

Third, many people find completing many small task more satisfying than one big task.  If you study five sets of ten flashcards instead of one set of fifty, you get four additional chances to feel good about your progress.  It's counterintuitive, but our brains often like many small rewards over one large one.  I dive into this topic in more detail in my article on rewards, which you can read here.  Interleaving is one way to set up multiple, recurring rewards without a lot of additional effort. ​

Many people like novelty.  We are attracted to things that are new.

This undoubtedly a good thing.  Curiosity, experimentation, and exploration propel our lives forward, both as individuals and collectively.  However, true master of any skill or topic requires engaged review of the material.  Review, by definition, is old stuff.  It's unsurprising that old information can feel dull, boring, or simply too familiar to need review.  This sense of oldness can be compounded if you always review the information in the same order.

It's a classic human conundrum.  When you're reading your notes, they seem familiar.  You pick up your flashcards to study.  But after awhile, you're just flipping through them without even reading them.  A playlist full of your favorite songs is significantly less awesome after a few repetitions.  Your brain has this sense that this is all old, and therefore, not really interesting or exciting.

Luckily, there is hope!  It doesn't take all that much to interject some newness into your routine.  Hitting the shuffle button can liven things up.  Adding new songs sometimes changes the whole tone of your playlist.  Interleaving works in much the same way.

First, interleaving purposely switches the order of events.  That way, you don't get used to seeing the same thing, in the same order, day after day.  Each study session has new information, or the information is presented in a new order.  You won't get used to the same the same-old-same-old if it isn't the same.  

Second, you don't study the same thing everyday, so your brain will naturally forget some things.  This may seem bad.  After all, we are studying to understand and remember information.  However, forgetting is necessary for long-term memory retention.  The more times you forget parts of the puzzle and review them, the stronger that information gets coded into your brain.  That's really helpful when it comes time to review for the big AP exams in May.  It also has the side benefit of making things more interesting. ​

Our memories are biased.  We don't remember everything equally well.  Instead, our brains are biased towards some information.  This information is more likely to be stored away for later use.  Interleaving takes advantage of two of these principles.

First up is the primacy bias.  You are more likely to remember the first thing you studied.

Second is the recency bias.  You are more likely to remember the last thing you studied.

The implication here is that our brains are not very good at storing information from the middle of a study session.  If you study the same thing in the same order, the "middle" information is always the same.  If the middle is very large, that's more potential for loss.

Interleaving forces us to take a big thing and break it into small things.  If we have a fifty card flashcard deck, there are forty cards that are in the "middle."  If we break that same deck into 10-card sets, then the "middle" of each set is minimized.  If we rotate the order we study those cards, then the same cards won't always be in the middle of your study session. ​

In AP US History and AP World History, connecting events together is a critical skill.  Historians understand the past by connecting events through causation, continuity and change, and comparison.  Every Long Essay Question and Document Based Question requires this kind of thinking.  It's also a key factor in earning the complexity point.

Our brains are wired to look for patterns.  But if related events are not presented together, it's harder to consider the relationship between them.  You can get some of these long-term connections through a good lecture or reading a quality textbook.  Interleaving also helps.  By shuffling up your study order, you'll naturally see new concepts presented next to each other.  This can reveal connections that would otherwise be obscured.

I help ambitious students improve their skills and master the AP exam.  Learn more here!

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