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Scholars Math 7.2: Introduction to Number Theory

Fundamental principles of number theory, including primes and composites, divisors and multiples, divisibility, remainders, modular arithmetic, and number bases.

12 weeks

Diagnostics

ARE YOU READY? DO YOU NEED THIS?

Documents

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

Schedule

Thursday
Mar 19 - Jun 4
7:30 - 9:00
PM ET
Mar 19 - Jun 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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
CLOSED
Sunday
Apr 19 - Jul 19
7:30 - 9:00
PM ET
Apr 19 - 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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Few Spots Left!
Tuesday
May 19 - Aug 4
7:30 - 9:00
PM ET
May 19 - Aug 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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Sunday
Jun 7 - Aug 30
7:30 - 9:00
PM ET
Jun 7 - Aug 30
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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Wednesday
Jun 17 - Sep 2
7:30 - 9:00
PM ET
Jun 17 - Sep 2
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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Monday
Jul 13 - Oct 5
7:30 - 9:00
PM ET
Jul 13 - Oct 5
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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Friday
Aug 28 - Nov 13
7:30 - 9:00
PM ET
Aug 28 - Nov 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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Sunday
Sep 20 - Dec 13
7:30 - 9:00
PM ET
Sep 20 - Dec 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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Monday
Oct 19 - Jan 25
7:30 - 9:00
PM ET
Oct 19 - Jan 25
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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL
Sunday
Dec 6 - Mar 14
7:30 - 9:00
PM ET
Dec 6 - Mar 14
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
$415 (~$35/lesson)
$470 w/books
$415 (~$35/lesson)
With Books $470
ENROLL

AoPS Holidays

There are no classes May 23 ‐ 25, July 3 ‐ 5, September 5 ‐ 7, October 31, November 23 ‐ 29, December 21 ‐ January 3, and February 13 - 15 2027.

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 Honors Math 7: Introduction to Algebra (Part 1) 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 Scholars Math 7.1: Introduction to Counting & 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 Text

Introduction to Number Theory
By Mathew Crawford
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: Scholars Math 7.2: Introduction to Number Theory

As the first online course I've ever taken, I can say without doubt that it has been a tremendously great experience. I know that a lot people that took Intro to Number Theory were still in grade school, but taking it as a senior in high school, I still feel challenged and frankly I don't feel the same kind of embarrassment I feel in a normal classroom when I don't understand the material or want to ask a question. The instructor was extremely knowledgeable and enthusiastic about the subject which made it all the more motivating to learn. Props to AoPS for such excellent classes!