Math videos for division, long division, factors, divisibility, and primes (grades 3-5)

Find here free online math videos on division, long division, factors, divisibility, and primes, meant for 3rd, 4th, and 5th grades.

Division with single-digit divisor (3rd grade)

These videos match topics in Math Mammoth Division 1 worktext (Blue Series).

The connection between multiplication and division

Divide evenly into groups — basic concept of division

Division versus multiplication word problems

Division by zero

Division with remainders

Long division (4th grade)

These videos match topics in Math Mammoth Division 2 worktext (Blue Series).

The order of operations plus writing simple expressions

The remainder, part 1

The remainder, part 2 – we learn to write division with a different symbol and learn about the remainder in word problems

How to teach long division

Long division — step-by-step examples (several videos)

Remainder problems – word problems involving long division with a remainder

Concept of average

Find fractional parts with division

Division (5th grade)

These videos match topics in Math Mammoth Multiplication & Division 3 worktext (Blue Series).

Review: Multiplication and Division – simple equations, bar models, terminology

Long division with a two-digit divisor

Long division as continued (repeated) subtraction

Divisibility, factors, and primes (grades 4-6)

These videos match the topics in Math Mammoth Factors & Factoring worktext (Blue Series).

Divisibility (and factors & multiples)

Divisibility rules

An introduction to prime numbers

Finding factors

Prime factorization using factor trees

The sieve of Eratosthenes (for finding primes)

Prime factorization

The greatest common factor

The least common multiple

How to use factoring to simplify fractions, and how to cross cancel