PrepLion is focused exam prep that helps you start, stay on track, and finish — calm, guided, and distraction-free, one question at a time. It covers the Digital SAT and ACT for college admissions, plus CLEP for college credit. The best prep tools usually cost hundreds of dollars or require hiring a tutor; PrepLion is free to start, with a real, calibrated pass probability for every student.
Built especially for students who get overwhelmed, distracted, or stuck just starting — but useful for everyone. Everyone begins in Focus Mode (one question, minimal screen, calm explanations). When you want the full toolkit — analytics, study plans, mock exams — Regular Mode is one tap away.
For college students, CLEP exams offer a way to skip intro courses and save thousands — but there's almost no quality prep out there beyond outdated practice books, and none of it tells you how close you actually are to passing.
We built PrepLion to solve that problem. A platform that does what a great tutor does: explain why, not just what — then test whether it clicked.
Sage is the result of that idea: a study partner that's available 24/7, never gets impatient, and adapts to exactly where you're struggling — whether you're aiming for CLEP College Algebra, Introductory Psychology, or your Digital SAT score.
Our Mission
“Give every CLEP candidate a real, calibrated pass probability — and the targeted practice to lift it — before exam day.”
Active recall. Research consistently shows that actively retrieving information — not passively rereading notes — is the most effective way to move knowledge into long-term memory. Every PrepLion practice question and every Sage comprehension check is an act of retrieval.
Spaced repetition. When you answer a question wrong, PrepLion schedules it to reappear at increasing intervals. This technique has been shown in cognitive science studies to dramatically improve retention over weeks and months compared to massed practice.
Mastery-based progression. Rather than assigning the same material to every student, Sage tracks your mastery by unit and generates questions targeting your weakest areas first. This approach — rooted in Bloom's mastery learning framework — ensures that practice time goes where it has the most impact.
Comprehension verification. After Sage explains a concept, it offers an optional 3-question check to verify you understood the explanation — not just read it. This closes the loop between passive learning and active demonstration of understanding.
Every CLEP practice question goes through a rigorous 9-step quality pipeline
Topic Distribution
Questions match College Board’s official exam topic weights
Bloom’s Taxonomy
50%+ questions test application and analysis, not just recall
Scenario-Based
80%+ of questions present real-world scenarios, matching CLEP’s format
Misconception-First Distractors
Wrong answers target actual student misconceptions
Question Generation
Questions are calibrated to intro-college difficulty level
Cross-Model Validation
A second model independently validates every question
8-Criterion Review
Factual accuracy, single correct answer, distractor quality, cognitive level, exam alignment, scenario check, distractor distinctness, explanation quality
Difficulty Calibration
Empirical tracking ensures questions match real CLEP pass rates
OpenStax Grounding
Factual accuracy verified against free, peer-reviewed college textbooks
34 College Board CLEP exam topic distributions aligned
120+ original calibration question stems validated against
PrepLion is not affiliated with or endorsed by the College Board. CLEP® is a registered trademark of the College Board.
Every question in the bank is checked before it can reach you. Our deterministic quality gates mechanically verify each item — answer-key consistency, a complete question stem, a present passage or stimulus where one is required, and in-scope content. On top of that, an independent answer-key re-solve audit re-answers questions from scratch to confirm the marked key is actually correct.
Deterministic gates
Answer-key consistency, stem completeness, required passage/stimulus, and scope — checked mechanically, every item.
Independent re-solve audit
Questions are answered fresh to confirm the marked answer key is the right one.
Public fidelity dashboard
We publish the standard openly, so you can see how the bank holds up — not just take our word for it.
We verify what we can and remove what we can't confirm. We're honest about the limits: PrepLion is not the official test maker, and no bank is perfectly error-free — but you should know exactly what we check and why.
See our question quality standardInstant Feedback on Every Answer
Every MCQ and FRQ gets an immediate explanation of why the correct answer is right and why each wrong answer is a common misconception. No waiting, no answer keys.
Mastery Tracking Across All Units
Your dashboard shows per-unit mastery percentages, accuracy trends over time, and a visual heatmap — so you always know exactly where to focus your next study session.
Adaptive Study Plans
Each week, your study plan targets your weakest units first and adjusts as your scores improve. Set your exam date and the plan counts down with you.
Here's what the experience looks like — from your personalized study plan to practice questions with instant feedback.
Master Units 4 & 5 before Friday
Focus Areas
Unit 4: Revolutions
41% mastery — 12 MCQs recommended
Unit 5: Cold War
63% mastery — 8 MCQs recommended
Unit 2: Exploration
74% mastery — 5 MCQs to reinforce
Mon: Unit 4 MCQs
Tue: Unit 5 Review
Wed: Mixed Practice
Thu: Weak Topics
Prioritized weekly plan by unit
MCQ · Unit 5: Revolutions
Which of the following BEST explains why the French Revolution spread ideas of democracy across Europe?
Napoleon's military campaigns (1799–1815) carried Revolutionary ideals of liberty and nationalism into conquered territories, abolishing feudal privileges across Europe.
Instant Sage explanations
73%
Pass Prob.
78%
Accuracy
12d
Streak
2,450
XP
Mastery by Unit
Accuracy Over Time
Per-unit mastery tracking
Outcome-Obsessed
We measure success in score improvements, not time-on-site.
Accessible First
Core features are free. Always. Premium is for students who want more — not a paywall for the basics.
Focused by Default
One question at a time, calm and distraction-free. Everyone starts in Focus Mode; the full toolkit is one tap away in Regular Mode.
CLEP (College Credit)
SAT (College Admissions)
ACT (College Admissions)
34
CLEP exams (college credit)
Digital SAT
College admissions
ACT
College admissions
24/7
Sage Live Tutor availability
$19
Pass plan/mo ($149/yr)
Every CLEP course plus the Digital SAT and ACT, with banks checked by deterministic quality gates and independent answer-key audits. Every approved question AI-reviewed against official past-exam content. Full dashboard activation overhaul, student-report auto-quarantine defense, and CLEP + SAT + ACT running on the same RAG-grounded generator pipeline.
Independently Re-Solved
Approved CLEP, SAT, and ACT questions pass an independent answer-key re-solve audit against official content descriptions. Rejected items stay un-approved, pending admin review. Grading is anchored in official content descriptions, not generic web content.
RAG-Grounded Question Generation
Each new question prompt injects 3–5 real CB exemplars as style/rigor/format targets. Multi-model consensus (Haiku + Groq) verifies the correct answer before the question is approved. Plagiarism guard rejects near-copies of exemplars.
Activation Overhaul (A23.4)
Zero-signal users now see "Warm up. See your level." with a 3-question 60-second challenge instead of a 15-question diagnostic. Evaluation happens AFTER engagement. Measurement instrumentation covers dashboard → coach-plan → CTA click funnel.
Student-Report Auto-Quarantine
Three unique-user reports on a single question and it's pulled from circulation immediately pending admin review. Prevents one bad question from compounding into public feedback. The primary defense against quality regressions.
Clutter-Free Dashboard (5 Cards)
Radical simplification from 14 cards to 5. One dominant CTA, state-shifting tone, Duolingo-style path progression, and a retention micro-win loop. Built on a single coach-plan response that's now the single source of truth for all dashboard signals.
Full Course Coverage
34 CLEP exams + the Digital SAT + the ACT. Every live course has its own blueprint-aware question pool, readiness engine, and coach-plan prescription.
Last-mile anxiety answers + TurboTax-style onboarding. CLEP-at-home pillar page, test-day hub pages, /faq 8 → 21 questions, SageFAQ test-day entries, trial-surfacing CTAs, Anthropic fallback on Sage chat, admin reset restores true fresh state.
Post-diagnostic lock-in, AI-as-SME question review pipeline, provider cost tracking, and Reddit v5 Resource Hub expansion — turning insight into action.
Post-Diagnostic Lock-In Modal
The moment your diagnostic finishes, a single decision: "Fix [weakest unit] now — 5 questions (2 min)." No scrolling past 7 sections to find the right action. Closes the insight-to-abandon cliff for new users like Jay Lee.
AI-as-SME Review Pipeline (Phase 1)
Admin can't be SME in all 56 subjects, so question review uses an AI-as-SME rubric with an audit trail. New QuestionReview schema records every review pass (model, score, verdict, reasoning). Validated end-to-end on 7 student-authored CLEP Biology questions.
Admin AI Usage Tracking
Per-provider 24h health card on the Admin Overview tab — call counts, success rates, average latency. Fire-and-forget instrumentation adds zero latency to user AI calls. Spot providers burning quota before the bill arrives.
Reddit v5: Resource Hub Expansion
Every CLEP course now in the Resource Hub with free-prep fact sheets. Every /am-i-ready/[slug] page has the Am I Ready CTA. Secondary "Ask r/clep instead" link on results — where the CLEP trust channel actually lives.
GA4 Measurement for Reddit + Post-Diagnostic
ask_reddit_click, result_shared, post_diag_cta_shown, post_diag_practice_clicked, post_diag_plan_clicked, post_diag_dismissed — the full measurement stack so we finally know what converts instead of guessing.
Test Infrastructure: 230 Unit + 13 E2E
Mock-gate, dashboard-resume, onboarding-full-flow, post-diagnostic-modal Playwright specs all green on production. Section D regression guards prevent the bugs we already fixed from coming back.
28,000 AI-reviewed questions, Sage tutor with Anthropic Direct, feedback system, military support, and 3-tier pricing.
AI-Reviewed Question Bank
Every question reviewed by Claude AI for accuracy. CLEP, SAT, and ACT courses aligned with official exam specs — correct question counts, timing, and content weights.
College Board Aligned
All 34 CLEP exams verified against official CB specifications. Correct timing per question (39s-123s depending on exam), accurate credit hours (3-6), and Financial Mathematics unit added to College Math.
3-Question Smart Start
New users get a 3-question warm-up (easy first) instead of 10. Micro-progress after each answer. Natural expand to 5 more questions. Reduces drop-off, builds confidence.
CLEP Savings Calculator
Interactive tool at /clep-savings showing how much you save with CLEP vs traditional tuition. Choose your school type, number of exams, see instant savings breakdown.
Feedback & Improvement Loop
In-app feedback popup lets students report issues, suggest features, and rate their experience. Sage FAQ schema for instant answers to common questions.
3 Pricing Tiers + Stripe Payments
Free (7-day trial, then: 15 practice questions/day with full explanations, 1 diagnostic + 1 mock, view-only plan), Pass Plan ($19/mo — unlimited), Fast Track ($49 one-time, 1 exam, 90 days). Stripe checkout with webhook-based account upgrades.
Foundation release: full course coverage, quality audit, difficulty calibration, mock exams, diagnostics, PWA, and full documentation.
34 CLEP exams
Choose your exam at signup. College Board-verified mock blueprints, topic weights, and real timing across every CLEP course.
College Board-Verified Mock Exams
5-exam progression journey matching official CLEP format — verified question counts, real timing, topic weights, multi-section support, and pretest questions.
19,330 Quality-Audited Questions
8-point automated audit: near-duplicate removal, topic diversity enforcement, Bloom's taxonomy, forbidden pattern detection, difficulty calibration matching real pass rates.
Diagnostic Test + Study Plans
15-minute diagnostic covering all units per course. Pass probability, weak/strong areas, estimated study hours, and AI-generated adaptive study plans.
PWA: Offline, Voice, Auto-Save
Works offline with cached questions. Text-to-speech on every question. Auto-saves mock exams and diagnostics. System dark mode detection.
College Board Research Applied
Phase A+B research: 200+ official samples analyzed, community reports from 16 exams. Exam-specific patterns enforced in question generation.
Have a question, found a bug, or want to suggest a course? We read everything — reply within 24 hours.
contact@preplion.aiFor pricing details, see the Pricing page.
CLEP® is a trademark registered by the College Board, which is not affiliated with, and does not endorse, this product or site. DSST® is a trademark owned by Prometric, which is not affiliated with, and does not endorse, this product or site.
PrepLion is an independent educational technology platform. All practice questions and study materials are original works created by PrepLion — not reproduced from any official exam publisher. Some content is generated using large language models. CLEP curriculum references use publicly available subject descriptions and freely licensed resources (OpenStax CC BY 4.0, Khan Academy, Wikipedia CC BY-SA).
PrepLion A23.4