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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

Wednesday
Jul 17 - Jan 15
7:30 - 9:00
PM ET
Jul 17 - Jan 15
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
CLOSED
Sunday
Aug 18 - Feb 23
7:30 - 9:00
PM ET
Aug 18 - Feb 23
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
3 spots left
Thursday
Aug 29 - Mar 6
7:30 - 9:00
PM ET
Aug 29 - Mar 6
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Friday
Sep 6 - Mar 7
7:30 - 9:00
PM ET
Sep 6 - Mar 7
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Tuesday
Sep 10 - Mar 11
7:30 - 9:00
PM ET
Sep 10 - Mar 11
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Sunday
Sep 29 - Mar 30
1:00 - 2:30
PM ET  
Sep 29 - Mar 30
1:00 - 2:30 PM Eastern
12:00 - 1:30 PM Central
11:00 - 12:30 PM Mountain
10:00 - 11:30 AM Pacific
Click here to see more time zones
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Sunday
Oct 27 - Apr 27
7:30 - 9:00
PM ET
Oct 27 - Apr 27
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Monday
Nov 11 - May 12
7:30 - 9:00
PM ET
Nov 11 - May 12
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Wednesday
Nov 13 - May 14
9:30 - 11:00
PM ET  
Nov 13 - May 14
9:30 - 11:00 PM Eastern
8:30 - 10:00 PM Central
7:30 - 9:00 PM Mountain
6:30 - 8:00 PM Pacific
Click here to see more time zones
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL
Tuesday
Dec 10 - Jun 3
7:30 - 9:00
PM ET
Dec 10 - Jun 3
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
$690 (~$29/lesson)
$755 w/books
$690 (~$29/lesson)
With Books $755
ENROLL

AoPS Holidays

There are no classes August 30 ‐ September 2, October 31, November 25 ‐ December 1, and December 21, 2024 ‐ January 3, 2025.

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

I really enjoyed taking my first AoPS class. I always thought that online classes weren't very good. I was mistaken after I took this class. Not only did Introduction to Geometry help me become a better math student, it also helped me to think more abstractly and look for multiple roads to solve a problem. I enjoy the way the classroom is run and the pace was very nice. The class wasn’t boring at all. This class challenged me to become a better thinker and was way more challenging than regular school courses. I am also very glad that AoPS also included a little bit of a social aspect to math with the message boards. I made a lot of friends through this course. In school, I am always made fun of for being ahead of all of the other students. On AoPS I actually feel accepted for once because I can interact with kids that are more advanced than I am and also I learn from them. I will definitely take another AoPS class.