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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

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
CLOSED
Sat & Sun
Sep 13 - Sep 14 		4:00 - 7:00
PM ET  –
Sep 13 - Sep 14
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
Ray Garner $150
$150
CLOSED
Sat & Sun
Apr 18 - Apr 19 		4:00 - 7:00
PM ET  –
Apr 18 - Apr 19
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
Carlos Bovell $150
$150
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.

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 this class! This online classroom provided all of the clarification I needed for Prealgebra. The challenge problems had me actually thinking and Alcumus really helped me practice the strategies that I was taught. I learned many, MANY things this year and I now understand things that I never understood before. The classes were very fun and engaging and went at the perfect pace. I also enjoyed having the transcripts to refer to when I had to miss a class or was in need of rereading some information that I'd forgotten. All in all, this was a SUPER great class and I am looking forward to joining Prealgebra 2!