What Kids Actually Miss: Accuracy Data from Real Practice Sessions

This study reports anonymized, aggregated accuracy from real practice sessions on iPrepGenius — which skills students miss most, by battery. No individual student data is ever shown; skills appear only once they have a statistically meaningful sample.

Hardest skills by observed accuracy

Methodology

Figures are computed live from the iPrepGenius question bank (311,000+verified, unretired practice questions at the time you loaded this page). Our banks are original practice content modeled on each test's published blueprint and format; they are not actual test items, and findings describe our bank's composition — a faithful proxy for, but not a publication of, the tests themselves. Difficulty ratings use our 1–5 scale assigned at generation and refined by calibration. Aggregated practice statistics, where shown, are fully anonymized. You're welcome to cite this study with a link.