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Introduction to Number TheoryFundamental principles of number theory, including primes and composites, divisors and multiples, divisibility, remainders, modular arithmetic, and number bases. |
12 weeks |
12 weeks ARE YOU READY? DO YOU NEED THIS? SYLLABUS |
Schedule
Friday
Sep 6 - Nov 22 |
7:30 - 9:00 PM ET
Sep 6 - Nov 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 |
Sindi Sabourin |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
CLOSED
With Books $455
|
Thursday
Oct 10 - Jan 23 |
7:30 - 9:00 PM ET
Oct 10 - Jan 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 |
Aaron Doman |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
CLOSED
With Books $455
|
Monday
Dec 2 - Mar 3 |
7:30 - 9:00 PM ET
Dec 2 - Mar 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 |
Chuck Garner |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
ENROLL
With Books $455
|
Tuesday
Jan 28 - Apr 15 |
7:30 - 9:00 PM ET
Jan 28 - Apr 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 |
Luis Ares |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
ENROLL
With Books $455
|
Sunday
Feb 16 - May 4 |
7:30 - 9:00 PM ET
Feb 16 - 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 |
Thinula De Silva |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
ENROLL
With Books $455
|
Monday
Mar 17 - Jun 9 |
7:30 - 9:00 PM ET
Mar 17 - Jun 9
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 |
Martha Maria Bernal Guillen |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
ENROLL
With Books $455
|
Thursday
Apr 17 - Jul 3 |
7:30 - 9:00 PM ET
Apr 17 - Jul 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 |
Jason Gorgia |
$400
(~$34/lesson)
$455 w/books
|
$400
(~$34/lesson)
ENROLL
With Books $455
|
AoPS Holidays
There are no classes November 25 ‐ December 1, December 21 ‐ January 3, May 24 ‐ 26, July 4 ‐ 6, August 29 ‐ September 1, and October 31, 2025.
Who Should Take?
This course is appropriate for students in grades 6-9 who have mastered basic algebra up through solving linear equations and manipulating multi-variable expressions. Students who have completed our Introduction to Algebra A course should have sufficient background. Students who are already proficient with modular arithmetic and basic Diophantine equations do not need this course. This course is roughly the same difficulty as our Introduction to Counting and Probability class. For those preparing for contests, this course should help with MATHCOUNTS and the AMC 8/10/12 tests.Lessons
1 | Integers, Fractions, Decimals, and Number Bases |
2 | Base Number Arithmetic |
3 | Multiples, Divisors, and Prime Numbers |
4 | Common Factors, Common Multiples, Euclidean Algorithm |
5 | Divisor Problems, More with the Euclidean Algorithm |
6 | Factorials, Special Integers, Algebra with Integers |
7 | Units Digit, Introduction to Modular Arithmetic |
8 | Calculations with Modular Arithmetic |
9 | Divisibility Rules and Multiplicative Inverses |
10 | Multiplicative Inverses, Solving Linear Congruences |
11 | Systems of Linear Congruences and the Chinese Remainder Theorem |
12 | Number Sense and Applications of Number Theory |
Required Textbook
Introduction to Number Theory
A thorough introduction for students in grades 7-10 to topics in number theory such as primes & composites, multiples & divisors, prime factorization and its uses, base numbers, modular arithmetic, divisibility rules, linear congruences, how to develop number sense, and more.
Related course: Introduction to Number Theory |