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Introduction to Geometry

Fundamentals of geometry, including angles, triangle similarity and congruence, complicated area problems, mastering the triangle, special quadrilaterals, polygons, the art of angle chasing, power of a point, 3-dimensional geometry, transformations, analytic geometry, basic trigonometry, geometric proof, and more.

24 weeks

Diagnostics

ARE YOU READY? DO YOU NEED THIS?

Documents

SYLLABUS
24 weeks ARE YOU READY? DO YOU NEED THIS? SYLLABUS  

Schedule

Sunday
Oct 26 - Apr 26
7:30 - 9:00
PM ET
Oct 26 - Apr 26
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Monday
Nov 3 - May 4
7:30 - 9:00
PM ET
Nov 3 - May 4
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Friday
Dec 5 - May 29
7:30 - 9:00
PM ET
Dec 5 - May 29
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Monday
Jan 5 - Jun 22
7:30 - 9:00
PM ET
Jan 5 - Jun 22
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Sunday
Jan 25 - Jul 19
7:30 - 9:00
PM ET
Jan 25 - Jul 19
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Wednesday
Feb 11 - Jul 22
7:30 - 9:00
PM ET
Feb 11 - Jul 22
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Thursday
Mar 5 - Aug 13
7:30 - 9:00
PM ET
Mar 5 - Aug 13
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Sunday
Mar 22 - Sep 20
7:30 - 9:00
PM ET
Mar 22 - Sep 20
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL
Tuesday
Apr 21 - Sep 29
7:30 - 9:00
PM ET
Apr 21 - Sep 29
7:30 - 9:00 PM Eastern
6:30 - 8:00 PM Central
5:30 - 7:00 PM Mountain
4:30 - 6:00 PM Pacific
Click here to see more time zones
$710 (~$30/lesson)
$775 w/books
$710 (~$30/lesson)
With Books $775
ENROLL

AoPS Holidays

There are no classes November 24 ‐ November 30, December 20 ‐ January 2, May 23 ‐ 25, July 3 ‐ 5, September 5 ‐ 7, and October 31 2026.

Who Should Take?

This is the most challenging of our Introduction series of classes. We recommend that students complete our Introduction to Algebra B course, or are able to pass the Introduction to Algebra B post-test, prior to taking Introduction to Geometry.

Lessons

1 Angles
2 Triangle Angles and Congruent Triangles
3 Isosceles & Equilateral Triangles, Perimeter, and Area
4 Similar Triangles
5 Similar Triangles and Right Triangles
6 More Right Triangles!
7 Special Parts of a Triangle
8 Special Parts of a Triangle, Continued!
9 Quadrilaterals
10 More Quadrilaterals
11 Polygons
12 Geometric Inequalities
13 Introduction to Circles
14 Circles and Angles
15 Tangents
16 Power of a Point
17 3D Geometry Part 1
18 3D Geometry Part 2
19 Transformations
20 Analytic Geometry
21 More Analytic Geometry
22 Basic Trigonometry
23 Problems!
24 More Problems!

Required Textbook

Introduction to Geometry
By Richard Rusczyk
A full course in challenging geometry for students in grades 7-10, including topics such as similar triangles, congruent triangles, quadrilaterals, polygons, circles, funky areas, power of a point, three-dimensional geometry, transformations, introductory trigonometry, and more.
Related course: Introduction to Geometry

This course was very helpful, and it was a great way to learn geometry. I had a lot of fun doing the problem sets and in class. Some of the problems were very challenging but it was very satisfying if I was able to solve them. I am very glad I took this course and am excited to move on to other math next year.