Khan Academy: Computational Number Theory: The Prime Number Theorem

Practice the techniques associated with number theory. This 5-page worksheet has many different types of problems for the students to solve and is a great component for any number theory unit8.

This video on changing improper fractions to mixed numbers would nicely compliment the Khan Academy video on writing mixed numbers as improper fractions. Sal first shows students how to convert improper fractions. Then, he uses drawings...

If your class has watched the Khan Academy video on recognizing divisibility, they will have a good foundation for this video on finding factors. Sal demonstrates how to find factors of a number by using the divisibility rules and...

Older elementary students will appreciate how clearly Sal explains how to find the prime factorization of 75. He shows the complete process, taking note of numbers that are, and are not primes, and why.

How can we improve the speed of a (deterministic) primality test?

Setting up the problem of a primality test.

Why is factorization hard, yet generating primes easy? Where do we go from here?

This video shows how to find the prime factorization of a two-digit number and write the answer in exponential notation. Practice problems available. Practice problems are available. [4:09]

Deepen the number sense of young mathematicians by exploring the process of prime factorization. Follow along with this step-by-step presentation that explains how factor trees are used to break a composite number down into its prime...

What is a prime number? Is zero a prime number? Is one a prime number? No?! Is two a prime number? Yes. So what is the definition of a prime number? A prime number is a number that can only be divided by 1 and itself. Watch this short...