A-Level · IGCSE · AP

Every mistake becomes an animated whiteboard lesson.

Sagacia marks your past papers like an examiner, then turns each mistake into a narrated, step-by-step animated explanation that starts from your own answer.

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From $14.99 per subject per month. Cancel anytime.

9709 · Paper 1 · ExampleMarked against the mark scheme

Find the minimum value of y = x² − 4x + 3 and state the value of x at which it occurs.

✓Completes the square: y = (x − 2)² − 1M1
✓x = 2A1
✓Minimum value −1A1
×Doesn't say it occurs when x = 20

0 / 4

Each mark point is checked against the official mark scheme, and mistakes that come up often in real classrooms are flagged.

Your mistake · whiteboard videoGenerated automatically

▶ Explanation · about 1 min 30 s

① Complete the square: y = (x − 2)² − 1

② Vertex (2, −1), opens upward

③ Minimum −1, when x = 2

▶0:42

As soon as marking is done, an animated whiteboard explanation of the mistake is generated, written and narrated step by step. Pause it, replay a step or ask a follow-up. Sciences and humanities alike.

Physics A2 · this classLive

Capacitance only 40% of the classPractice questions have been set automatically for these students

WeakNeeds workSecureMastered

Sample data

Our signature feature

Animated explanations, made for your mistake

Most tools tell you the right answer. Sagacia shows you where your working went wrong: a whiteboard animation with voice-over is written and narrated step by step, from your answer to the correct method. Pause it, replay a step, or ask a follow-up question and the explanation continues. It works for maths and sciences, and for graphs and essays in economics and the humanities.

What you can do

Practice that tells you what to fix

Built with experienced exam teachers for students who revise on their own.

Past papers, marked as you finish

Sit real past papers online. Objective questions are checked instantly; written answers are marked against the mark scheme, part by part.

See exactly where the marks went

Feedback follows the method, accuracy and reasoning marks examiners use, so you know which step cost you the mark, not just the final score.

A practice report you can act on

Sit a full mock paper and get your practice score with a topic-by-topic breakdown of what to revise first.

Explanations for your own mistakes

For a question you got wrong, watch a short whiteboard walkthrough with voice-over that starts from your answer, then ask follow-up questions.

Practice on the topics you choose

Pick a syllabus topic and difficulty and get fresh questions, marked the same way as the real papers.

Photograph handwritten work

Do the paper on paper, take a photo, and get it marked page by page.

How it works

From sign-in to focused revision in four steps

Sign in with your email

No Chinese phone number or app needed. We send a 6-digit code.

Choose your courses

Tell us your exam board and subjects.

Do a paper or practise a topic

Online or on paper with a photo.

Fix what the marking shows

Use the explanations and targeted practice, then sit another mock paper to see how your practice score moves.

Subjects

Exam boards and courses

Coverage differs by subject and paper. You can see what is available for your course after you sign in, before you pay for anything.

Cambridge International A Level

MathematicsFurther MathematicsPhysicsChemistryBiologyEconomicsComputer SciencePsychologyBusinessAccounting

Cambridge IGCSE

MathematicsAdditional MathematicsPhysicsChemistryBiologyEconomics

Pearson Edexcel International A Level

MathematicsFurther MathematicsPhysicsChemistryBiologyEconomics

AP · 21 courses

Calculus ABCalculus BCPrecalculusStatisticsPhysics 1Physics 2Physics C: MechanicsPhysics C: Electricity and MagnetismChemistryBiologyEnvironmental ScienceComputer Science AComputer Science PrinciplesMicroeconomicsMacroeconomicsPsychologyEnglish Language and CompositionUnited States HistoryWorld History: ModernHuman GeographyArt History

Pricing

Two plans, per subject

Standard ($14.99 a month) gives you AI marking, written explanations and practice. Animated ($59.99 a month) adds animated whiteboard explanations with voice-over, follow-up questions and photo marking. Cancel anytime.

See the full price list

For your own practice

A study tool, not an assessment

Sagacia is for students revising on their own. Its marks, scores and feedback are self-study aids for you only: they are not official results, are not shared with schools, universities or anyone else, and are not used to make any decision about you, such as admission, placement, awarding grades or predicted grades.