🧪 Educational Instructional Design Simulation

One of the most consequential decisions an instructional designer makes is not what to teach but in what order to schedule practice. This simulator models the well-documented interleaving effect: four geometry problem types are practiced either blocked (all of one type before moving to the next) or interleaved (types mixed trial-by-trial), each trial building a surface "retrieval strength" and a deeper "discrimination strength" at different rates depending on whether the learner had to switch strategies. Practice accuracy is tracked live as the towers grow in a real 3D scene, and pressing "Test After Delay" applies an exponential forgetting curve whose decay rate itself depends on discrimination strength — revealing the classic finding that blocked practice feels easier and scores higher during the session, while interleaved practice usually wins on the test that actually matters: the one taken after time has passed.