When CORE Need Not Be Too CORE:

How “Difficult” Strategies Actually Fit the Framework

The CORE Framework (Concise, Organized, Relevant, Engaging) is built on a deceptively simple idea: the best teaching strips away noise, sequences learning with care, ties content to students’ goals, and keeps them meaningfully involved. In other words, CORE helps educators build a clear path for students to walk.

But here’s the paradox: some of the most powerful evidence-based learning strategies don’t make that path easier—they make it intentionally harder. Research shows that learning is deeper and longer-lasting when students must wrestle with difficulty, unpredictability, and generative thinking.

At first glance, this seems at odds with CORE. How is it concise to make something harder? How is it organized to shuffle topics out of order? How is it engaging to ask students to work harder than they expect?

The answer is that these strategies don’t violate CORE—they refine it. They represent what happens once the foundation is set. Let’s take a closer look at three: desirable difficulties, interleaving, and generative learning.

Desirable Difficulty: The Power of Struggle

The term “desirable difficulty” comes from Robert Bjork and Elizabeth Bjork, who demonstrated that introducing the right kinds of obstacles into the learning process leads to stronger memory and transfer of skills.

Examples include:

• Spacing practice across time instead of massing it into a single session.
• Retrieval practice (testing yourself) instead of re-reading notes.
• Varying conditions of practice (solving problems in different contexts).

At the moment of learning, students often feel these methods are less efficient. They may even say, “I don’t get it—I was doing better before.” But when tested later, they outperform those who learned under “easier” conditions.

Where this fits in CORE:

• Concise: Desirable difficulties do not add clutter; they remove false ease. Instead of flooding students with redundant practice, you create targeted challenges that force them to focus their energy where it matters.
• Engaging: When students realize that struggling today leads to mastery tomorrow, they develop persistence and confidence. The key is making the difficulty desirable, not discouraging.

Example: In a physical therapy classroom, instead of giving students one patient scenario and letting them repeat the same gait training intervention 10 times, an instructor might vary the cases slightly—different comorbidities, different home environments, different patient goals. The learner stumbles more, but ultimately becomes more adaptable and competent.

Interleaving: Organized Disruption

Traditional practice often uses blocking—students do one type of problem at a time until they “get it.” The problem is, blocked practice creates an illusion of mastery that vanishes when contexts change.

Interleaving—mixing different problem types or topics in a practice set—feels more confusing in the moment, but it forces learners to identify which strategy applies, not just how to execute it. This leads to better discrimination and transfer.

Where this fits in CORE:

• Organized: On the surface, interleaving seems to break the “organized” pillar. But true organization isn’t about predictability; it’s about purposeful sequencing. Interleaving is highly organized when mapped to long-term goals, even if it feels messy in the moment.
• Relevant: Real life rarely hands us one type of problem at a time. By mixing cases, interleaving mimics the complexity of professional practice, making learning immediately more applicable.

Example: In a statistics course, instead of practicing 20 regression problems followed by 20 ANOVA problems, students might alternate between them. In a PT curriculum, students might practice transfers with patients who differ not just in diagnosis but in home setup, cognitive status, and safety risks—preparing them for the reality that no patient is “by the book.”

Generative Learning: The Learner as Teacher

Generative learning requires students to actively create meaning rather than passively consume it. Richard Mayer and Logan Fiorella identify strategies such as:

• Self-explaining (talking through one’s reasoning).
• Summarizing (condensing material in one’s own words).
• Teaching others (peer instruction or presentations).

These methods deepen processing and encourage learners to integrate new knowledge with prior understanding.

Where this fits in CORE:

• Concise + Relevant: By asking learners to generate meaning, you reduce dependence on dense lecture notes and help students see the direct connection to their goals.
• Engaging: Generative tasks shift students from passive recipients to active creators. This not only increases motivation but also builds confidence in applying knowledge beyond the classroom.

Example: Instead of simply reading about fall-risk factors in the elderly, students might create an infographic for caregivers, explaining gait speed as a predictor of falls. By generating this product, they process the information at a deeper level than memorization alone.

Why These “Violations” Are Actually CORE in Action

It’s tempting to think of CORE as always making learning easier. But that’s not its purpose. CORE makes learning clear. Once unnecessary barriers are removed, educators can introduce productive barriers that lead to mastery.

• Concise: Strip away clutter, but allow room for targeted challenges.
• Organized: Sequence content deliberately, even if that means weaving topics together.
• Relevant: Connect difficulties to real-world meaning, so students see why the challenge matters.
• Engaging: Support students as they struggle, making persistence rewarding rather than punishing.

When used well, strategies like desirable difficulty, interleaving, and generative learning transform CORE from a framework of clarity into a framework of depth.

Final Thoughts

The CORE Framework is not about making learning simple—it’s about making it purposeful. Strategies that at first appear to complicate learning are, in fact, essential tools for building expertise.

When instructors combine the clarity of CORE with the rigor of evidence-based strategies, they achieve the best of both worlds: students who not only understand the material but retain it, transfer it, and use it when it matters most.

In short: CORE lays the path. Desirable difficulty, interleaving, and generative learning build the muscle to walk it well.

References

Bjork, R. A. (1994). Memory and metamemory considerations in the training of human beings. In J. Metcalfe & A. P. Shimamura (Eds.), Metacognition: Knowing about knowing (pp. 185–205). MIT Press.

Bjork, R. A., & Bjork, E. L. (2011). Making things hard on yourself, but in a good way: Creating desirable difficulties to enhance learning. In M. A. Gernsbacher, R. W. Pew, L. M. Hough, & J. R. Pomerantz (Eds.), Psychology and the real world: Essays illustrating fundamental contributions to society (pp. 56–64). Worth Publishers.

Fiorella, L., & Mayer, R. E. (2016). Learning as a generative activity: Eight learning strategies that promote understanding. Cambridge University Press.

Rohrer, D., & Taylor, K. (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35(6), 481–498. https://doi.org/10.1007/s11251-007-9015-8 (opens in a new tab)

Rohrer, D., & Pashler, H. (2010). Recent research on human learning challenges conventional instructional strategies. Educational Researcher, 39(5), 406–412. https://doi.org/10.3102/0013189X10374770 (opens in a new tab)