A student reading and working through a problem

Grades 9–12

Your child's own
world‑class geometry tutor

Pioneered by Stanford AI researchers and learning scientists, Aristotle is the world's first voice-based AI geometry tutor. From first proofs through circles and trigonometry, Aristotle has improved thousands of grades over 22% within a week.

Trusted by families at

StuyvesantHunter College HSBronx ScienceBrooklyn TechHorace MannTrinity SchoolCollegiateBrearleyFieldstonHarkerCastillejaMenlo SchoolHead-RoyceLick-WilmerdingLowell HSMission San Jose HS

Fits your child's geometry class

State, school, or home aligned curriculums

State standards

Every geometry skill is aligned to Common Core standards, including the transformations-based approach most schools now teach, so tutoring matches what your child is graded on.

Your child's school

Share the syllabus or textbook and sessions follow your child's actual class, whether that's public, private, or homeschool.

Your own goals

Working toward a placement exam, an honors class, or getting a grade up? Aristotle builds the path backwards from your goal.

Features

All the tools of a great tutor.

Talk things through, work side by side, and come back next time to a tutor who remembers where you left off.

Learn out loud

Ask questions out loud, hear explanations in Aristotle’s voice, and interrupt whenever you need to.

An interactive whiteboard

Aristotle draws steps, diagrams, and images to help you learn visually.

Practice built for you

Get practice problems tailored to the exact topics you’re struggling with.

65 subjects and counting

From middle-school math to AP exams to SAT/ACT prep. We also build custom plans matched to state standards and specific courses.

Review with ease

Revisit session summaries, session whiteboards, and uploads in one place.

Upload your own materials

Aristotle can read and navigate any PDFs and images with the learner. That includes textbooks with hundreds of pages!

Personalized tracking

We break all subjects down into granular skills, then track mistakes and mastery on each one. Parents can see the whole picture at a glance.

A tutor that knows you

Aristotle remembers every session: what you’ve covered, where you got stuck, how you like things explained. It picks up right where you left off.

The curriculum

Over 190 geometry skills, personalized to your child

Aristotle is designed to always know what to teach at exactly the right time.

Sample curriculum

+ 9 more math subjects available

Not startedIn progressMastered* Click a topic to see the skills inside

* Click a topic to see the skills inside

Foundations of Geometry

Reasoning and Proof

Parallel and Perpendicular Lines

Transformations

Triangle Congruence

Relationships in Triangles

Quadrilaterals and Polygons

Similarity

Right Triangles and Trigonometry

Circles

Coordinate Geometry

Solid Geometry and Measurement

Probability

Geometry tutoring curriculum194 skills across 13 units

Foundations of Geometry

Lean on-ramp for the course: precise definitions and notation for points, lines, planes, segments, rays, and angles; segment and angle measurement and addition; coordinate midpoint and distance tools; angle pairs; and the core compass-and-straightedge tool constructions of the cross-cutting geo.construct.* family. Topics: Definitions and Notation, Segment Measurement, Angle Measurement, Angle Pairs, Coordinate Tools: Distance and Midpoint, Core Constructions.

Reasoning and Proof

Proof grammar practiced on easy content: conditional statements and their logical equivalents, inductive versus deductive reasoning, postulates and diagram conventions, and proof formats applied to algebraic, segment, and angle arguments. Topics: Conditional Statements and Logic, Proof Foundations and Formats.

Parallel and Perpendicular Lines

Transversal angle relationships and their proofs, criteria for proving lines parallel or perpendicular, and the coordinate side: slope criteria and equations of parallel and perpendicular lines, placed here with their conceptual basis ahead of the late Coordinate Geometry unit. Topics: Angles Formed by Transversals, Proving Lines Parallel, Perpendicular Lines, Slope Criteria and Equations of Lines.

Transformations

Rigid motions only: performing and describing translations, reflections, and rotations, the properties they preserve, compositions, symmetry, and congruence defined by rigid motions. Topics: Performing and Describing Rigid Motions, Compositions of Rigid Motions, Symmetry, Congruence via Rigid Motions.

Triangle Congruence

The first major synthesis: triangle angle theorems, congruence criteria (SSS, SAS, ASA, AAS, HL) justified by rigid motions, isosceles and equilateral triangle theorems, and congruence proofs with CPCTC. Topics: Triangle Angle Theorems, Congruence Criteria, Congruence Proofs.

Relationships in Triangles

Perpendicular and angle bisectors as loci, the four classical triangle centers, the midsegment theorem, and triangle inequality reasoning including the hinge theorem. Topics: Bisectors as Loci, Triangle Centers, Midsegments, Triangle Inequalities.

Quadrilaterals and Polygons

Polygon angle sums, parallelogram properties and proofs, special parallelograms, trapezoids and kites, and classification within the quadrilateral hierarchy. Topics: Polygon Angle Sums, Parallelograms, Rectangles, Rhombi, and Squares, Trapezoids and Kites, The Quadrilateral Hierarchy.

Similarity

The central relation changes from congruence to proportionality: dilations and their properties open the unit, then similarity defined via transformations, the AA/SSS/SAS criteria, proportionality theorems, and similar right triangles with geometric mean as the bridge into trigonometry. Topics: Dilations, Similar Figures and Criteria, Proportionality Theorems, Similar Right Triangles and Geometric Mean.

Right Triangles and Trigonometry

Pythagorean theorem and converse, special right triangles, and right-triangle trigonometry built on similarity, with elevation and depression applications. Topics: Pythagorean Theorem, Special Right Triangles, Right-Triangle Trigonometry, Trigonometry Beyond Right Triangles.

Circles

Central and inscribed angle relationships, chords, tangents, secants, segment products, circle proofs, arc length, sector area, and the radian connection, plus the circle constructions of the cross-cutting geo.construct.* family. Topics: Circle Vocabulary and Similarity, Angle and Arc Relationships, Chords, Tangents, and Segment Lengths, Circle Proofs, Arc Length, Sectors, and Radians, Circle Constructions.

Coordinate Geometry

The coordinate-methods unit: circle equations derived from the Pythagorean theorem, parabola focus and directrix work, partitioning directed segments, perimeter and area in the plane, and coordinate proofs that combine these tools with earlier figure properties. Topics: Equations of Circles, Parabolas from Focus and Directrix, Partitioning Segments, Coordinate Computations with Figures, Coordinate Proofs.

Solid Geometry and Measurement

Two-dimensional area including regular polygons and composites, cross sections and solids of revolution, volume formulas with informal derivations (including Cavalieri's principle), similar-solid scaling, and density and design modeling as the course's applications capstone. Topics: Area of Polygons and Composite Figures, Cross Sections and Solids of Revolution, Volume, Modeling with Geometry.

Probability

Conditional probability with sample spaces, events, independence, two-way tables, and the addition rule, plus geometric probability and counting methods as further extensions. Topics: Sample Spaces and Events, Independence and Conditional Probability, Geometric Probability and Counting.

Here’s what families say about Aristotle

My son told me yesterday that we should cancel his human tutor, because Aristotle is doing a better job. The human tutor was $250/hour.

Kim L.

parent of Andy, 13Milwaukee, Wisconsin

Common questions about online geometry tutoring

A few things you might wonder before getting started.

What does Aristotle's geometry course cover?

The full high school geometry sequence: 194 individually tracked skills across 54 topics, from foundations and proof through parallel lines, transformations, triangle congruence, similarity, right triangle trigonometry, circles, coordinate geometry, and solid geometry. Aristotle always knows which skills your child has mastered and what comes next, so every session picks up exactly where the last one ended.

Can Aristotle help with geometry proofs?

What does a geometry tutoring session look like?

How much does Aristotle cost compared to a private geometry tutor?

How is Aristotle different from ChatGPT for geometry help?

Can parents see how the tutoring is going?

Can Aristotle help if my child is struggling in geometry?

What if my child is in honors geometry or wants to move faster?

Does Aristotle follow my child's school geometry curriculum?

From the notebook

Check out our most recent blog posts.

A learner having an idea, surrounded by maps and equations

This could be you

A little help. A lot to learn.

For homework, supporting your child, or anything you’ve always wanted to know more about, Aristotle makes it easy for anyone to learn out loud.