This post has been revised to incorporate all the suggestions in the comments below, plus many more activities. Please update your bookmarks:
Or continue reading the original article…
(1) Use it as a number line to do addition and subtraction beyond what your child can handle mentally. Develop mental math skills by showing how to add or subtract the tens first (counting up or down) then the ones (counting left or right.)
(2) Look for addition and subtraction patterns. 5+7=? Now go to 25+7, 35+7, 65+7. What do you notice? What do 13-6, 23-6, 53-6, etc. have in common? Find other patterns.
(3) Look for counting-by (multiplication) patterns. Colored disks are nice for this, or M&M’s, or simple pinto beans. Mark the numbers you hit when you count by 2. What pattern do they make? Make the counting-by-3 pattern, or the 8’s, or others. Some of these are really neat, and you may want to print several charts so you can color them in. Why does the counting-by-5 pattern look like it does?
(4) Count by whatever number you want, but start at an unusual place. Count by 5, starting at 13. Or count by 2, but start with 47. Or, as Lim Ee Hai suggested below, count down by the number of your choice.
(5) Mark the multiplication patterns by putting colored dots along one edge or corner of each square. (That is, all the multiples of 2 get a yellow dot, for instance, and the multiples of 3 get green ones…) Which numbers have the most dots? Which numbers have just one? Which don’t have any?
(6) Play a number bonds game. Take turns pointing to any number. The other player has to say how many more it takes to make 100.
(7) What number is 1/2 of 100? How do you know? What number is 3/4 of 100? Are you sure? How can you show it is true? (What does the fraction 3/4 mean? What does any fraction mean?) What other fractions of 100 can you find? 1/10? 2/5? Can you find a number that is 1/3 of 100?
I am sure there are other things to do, but that is all I can dig out of my gray cells right now. These ought to keep you busy for quite awhile, though.
This is post #1 in my Hundred Board Series.