Two Study Habits Beyond Flashcards and Spaced Review

Spaced repetition and active recall get most of the attention in study advice, and for good reason, but a practice guide published by the Institute of Education Sciences (IES), the research arm of the U.S. Department of Education, lists several other evidence-backed recommendations that get far less attention. Two of them are easy to build into regular homework or test prep: interleaving worked examples with practice problems, and asking deep explanatory questions instead of only surface-level ones.

What the practice guide actually is

The guide, "Organizing Instruction and Study to Improve Student Learning," was written by a seven-person panel of cognitive scientists and education researchers for the IES's National Center for Education Research, and each recommendation in it carries an explicit evidence rating of strong, moderate, or low based on how much experimental support it has. This is a different kind of source than a single study or a blog summary: it is a synthesis of a large body of published research, reviewed and rated by subject-matter experts specifically for practical classroom and self-study use.

Habit one: interleave worked examples with problems you solve yourself

The guide's second recommendation states: "Have students alternate between reading already worked solutions and trying to solve problems on their own." This is called interleaving, and the practice guide rates it as having moderate evidence behind it.

The specific mechanic matters here. Rather than reading five worked examples in a row and then attempting five problems in a row (the common textbook structure), you alternate: read one worked example, immediately attempt a similar problem yourself, then read another worked example, then attempt another problem, and so on. The guide also makes a point about adjusting this ratio over time: "As students develop greater expertise, reduce the number of worked examples provided and increase the number of problems that students solve independently." In other words, interleaving is not a fixed 50/50 split forever; it should shift toward more independent problem-solving as you get more comfortable with the material.

This is a different kind of mixing than the more commonly discussed "interleaved practice problems" (alternating between different problem types within a practice set). The guide's version of interleaving is specifically about alternating between watching a solution get worked out and doing the work yourself, which keeps you from either passively reading through a stack of examples without engaging, or getting stuck and frustrated on unfamiliar problems with no model to reference.

Habit two: ask deep explanatory questions

The guide's seventh and final recommendation is rated "Strong," its highest evidence category: "Use instructional prompts that encourage students to pose and answer 'deep-level' questions on course material." The guide explains that these questions "enable students to respond with explanations and support deep understanding of taught material," distinguishing them from shallow factual-recall questions (what happened, when, or who).

A deep explanatory question asks why or how, not just what. For a history topic, a shallow question is "In what year did the event happen?" A deep question is "Why did this event happen when it did, and what would have had to be different for it not to happen?" For a science topic, a shallow question is "What is the formula?" A deep question is "Why does this formula work, and what would break if one part of it were removed?"

The guide notes this recommendation works best once you already have some basic factual and conceptual grounding in a topic; asking yourself "why" questions about material you have not yet learned the basics of is less productive than asking them once you have the foundational facts in place and are ready to connect them.

How these two habits fit together

Used together, these two habits form a natural progression through a single study session. Start by reading a worked example (step one of interleaving). Before moving to the next worked example, stop and ask a deep question about it: why did this particular step come next, and what would happen if the numbers or conditions were different? Then attempt a similar problem yourself, using the worked example as a reference rather than a full solution key. This combines the moderate-evidence benefit of interleaving (alternating input and practice) with the strong-evidence benefit of deep questioning (connecting individual steps to underlying reasoning), rather than treating them as two unrelated techniques.

A simple way to start using both this week

• Pick one topic you are currently studying from worked examples (a textbook chapter, a set of solved problems, a tutorial).
• Alternate rather than batch: read one worked example, then immediately try a similar problem without looking at the solution, then move to the next worked example.
• After each worked example, write down one "why" question about a step that was not obvious, and try to answer it before moving on.
• As you get more comfortable with the topic, shift the ratio, reading fewer worked examples and attempting more problems independently, per the guide's own recommendation.
• Keep your deep questions specific to a step or decision, not the whole topic; "why did they choose this method instead of another one" is more useful than a broad "why does this work."

Key takeaways

• Interleaving worked examples with your own practice problems (reading one, then solving one, rather than batching each type) carries moderate evidence according to a federal education practice guide.
• As you gain expertise in a topic, the guide recommends shifting the ratio toward more independent problem-solving and fewer worked examples.
• Asking deep explanatory "why" and "how" questions, rather than shallow factual-recall questions, is the guide's single most strongly evidenced recommendation.
• Deep questioning works best once you already have basic facts and concepts in place to connect together, not as a replacement for learning the basics first.
• Combining the two, alternating worked examples with your own attempts and pausing to ask "why" after each example, builds a single study routine out of two separately evidenced habits.