Prime Checkbox Activity

    Yes, a prime number is a number which is only divisible by 1 and itself, but before you read the MATH SPOKEN HERE! definition, complete this activity.

    A video is linked here and through the image at the left.

Step 0: Choose to mark your table of numbers digitally on the left or on paper after printing the table (after clicking it)

on the right.

1st: Do not read the definition of prime or prime factorization.  Do this activity first.

2nd: Because 1 is not a prime, and 1 is not composite, do nothing to the 1 checkbox.

3rd: The next number is 2. Because 2 is prime, SKIP the 2 box.

3rd: Check the box of every multiple of 2.

4th: The next number is 3. It is prime, because it is not a multiple of 2.

5th: SKIP the 3 box, but check the box of every multiple of 3.

6th: Repeat this procedure.

Go to the next number.

It is prime.  It is prime because it is not a multiple of the smaller primes.

DO NOT CHECK ITS BOX.

DO CHECK the boxes of each of its multiples.

Go on to the next number, if it is not checked, it is prime. DO NOT CHECK ITS BOX.

Check the box of every one of its multiples.

7th: When you have checked or skipped all numbers in the table, you will have check all composite numbers.

The unchecked boxes are those of prime numbers.

8th: See the pages listed at the bottom of this page for more information about prime numbers.