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Free K-12 Education for Everyone
A public, no-login-required library of textbooks for grades K through 12, aligned with SAT and ACT standards.
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Number recognition, Letter sounds, Observation skills
Addition and subtraction, Reading fluency, Scientific observation
Three-digit operations, Paragraph writing, Scientific inquiry
Multiplication and division, Reading comprehension, Scientific method
Multi-digit operations, Research skills, Scientific reasoning
Fraction operations, Argument writing, Scientific inquiry
Ratios and rates, Close reading, Experimental design
Proportional reasoning, Rhetorical analysis, Scientific modeling
Linear equations and systems, Complex text analysis, Physical science
Algebra I mastery, Literary analysis, Biology
Geometry and coordinate geometry, Synthesis and rhetoric, Chemistry
Algebra II and Precalculus, SAT/ACT R&W mastery, Physics
Precalculus and Statistics, College writing, Independent research
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All content is freely available. No paywalls, no subscriptions.
SAT/ACT Aligned
Every lesson is tagged with relevant SAT and ACT domains.
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Progress Simulator
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Zip Code Comparison
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Adaptive Tests
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Practice Tests
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AI Writing Tests
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Book Writing Practice
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Premium SAT/ACT Tests
Full-length official-style tests with detailed scoring and percentile estimates. $10/test.
AI SAT Test Prep
Full-length AI-generated SAT with detailed scoring, study plan, and improvement recommendations. $10/test.