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Before Prealgebra Ready for Prealgebra After Prealgebra Some Algebra 1 After Algebra 1 After Geometry After Algebra 2 After Precalculus Beyond Calculus
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Paradoxes and Infinity

In this class we'll explore several popular paradoxes and attempt to wrap our brains around the world of infinity. For example, we'll discover a hotel that's never full: somehow, this hotel can always add another guest, or two, or three. We'll also run into paradoxes about goats, haystacks, pop-quizzes and more. If you're interested in mind-bending ideas and theories and have a background in basic algebra, this class is for you!

6 hours
6 hours  

Schedule

Sat & Sun
Apr 12 - Apr 13 		4:00 - 7:00
PM ET  –
Apr 12 - Apr 13
4:00 - 7:00 PM Eastern
3:00 - 6:00 PM Central
2:00 - 5:00 PM Mountain
1:00 - 4:00 PM Pacific
Click here to see more time zones
Aaron Doman $150
$150
ENROLL
Mon, Tue, Wed & Thurs
Jul 14 - Jul 17 		7:30 - 9:00
PM ET
Jul 14 - Jul 17
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
Josh Zucker $150
$150
ENROLL

AoPS Holidays

There are no classes May 24 ‐ 26, July 4 ‐ 6, August 29 ‐ September 1, October 31, November 24 ‐ November 30, and December 20, 2025 ‐ January 2, 2026.

Topics

1 Paradoxes in Philosophy
2 Paradoxes in Mathematics
3 Hilbert's Grand Hotel and Infinite Cardinals
4 Zeno's Paradox of Dichotomy

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.