Methodology

1. Spaced repetition for vocabulary and missed questions, using the SM-2 algorithm (the basis of Anki). Reviews due at 1, 3, 7, 14, 30+ days based on rating.
2. Interleaved practice in the Daily Challenge: 5 reading + 5 math, mixed. Research shows interleaving yields ~77% retention vs. ~38% for blocked practice at 24 hours.
3. Mandatory error analysis: every wrong answer is categorized (didn't know concept, misread, ran out of time, arithmetic slip, wrong strategy, guessed). Pattern visualization shows the dominant mistake type.
4. IRT-lite mastery scoring: easy/medium/hard questions weighted 1.0/1.5/2.5. A topic isn't mastered until the student handles hard questions reliably.
5. Realistic mock conditions: four sections (English, Math, Reading, Science) with per-section timers totaling ~2.5 hours, navigation panel, flag-for-review, auto-submit on timeout — matching the PreACT 9 Secure (which allows a calculator in Math only).

The choices above are not invented; they come from cognitive science literature on retention and skill acquisition. Selected references:

• SuperMemo SM-2 algorithm (Wozniak, 1990) — the basis of every modern spaced-repetition system.
• Rohrer & Taylor (2007) on interleaved practice in mathematics.
• Roediger & Karpicke (2006) on the testing effect (retrieval practice).
• Item Response Theory (Lord, 1980) for difficulty-weighted scoring.
• Self-Determination Theory (Ryan & Deci, 2000) for our streak/freeze mechanic and mastery-tied (not vanity) achievements.

CPS does not publish official HSAT items, and we do not have access to retired test items. Our practice questions are:

• Original CC0 questions written to mirror HSAT structure and difficulty.
• Adapted from public-domain state assessments aligned to the same 8th-grade Common Core standards: NYSED Grade 8 ELA & Math, Massachusetts MCAS, Illinois IAR, Smarter Balanced.

Each question carries a source and license field visible in the explanation. We claim our practice mirrors the real test in format and difficulty distribution; we do not claim it shares actual content.

• We do not use leaked or retired HSAT items. There aren't any publicly available; if there were, using them would be unethical.
• We do not use shallow gamification (XP bars, badges for opening the app). 8th-graders see through that.
• We do not claim a guaranteed score. Score depends on practice consistency, baseline ability, and test-day variance.
• We do not collect any data on the server. We have no idea who uses the app or how.
• We do not advertise. There are no third-party scripts in the app — Lighthouse confirms zero trackers.

The CPS test is now the PreACT 9 Secure, scored on the ACT scale. The score report shows:

• Each section (English, Math, Reading, Science) on a 1–32 scale — an estimate from your raw score, since no official raw-to-scale table is public.
• A composite that averages the four section scores (also 1–32).
• Your 7th-grade core grade points (A = 112.5, B = 75, C = 38, D/F = 0; max 450) for context — admissions stay 50% test + 50% grades.

We deliberately do NOT show a single admission-point total or a PreACT cutoff: CPS has not published how a 1–32 score converts into points (expected near the start of 2026–27). Everything we show is labeled as an estimate, not a guarantee.

If you spot a question with an incorrect answer or explanation, or if CPS publishes new information about the HSAT format, please open an issue or contact us. We update the question bank in batches; bug fixes ship within a few days when reported.