


The Wonder Number Lessons
Lesson No. 2: Comparison The concepts of odd and even, greater than or less than, and place value are critical components to a future comprehension of all mathematics. Using the Wonder Number Board to introduce and reinforce these concepts will give your students a better overall understanding of the relationships between all numbers. The first comparison we make on the board is between odd and even numbers. To begin, explain that all even numbers are divisible by 2, and odd numbers are not. Place chips on all the multiples of 2 from 2 to 100. All numbers covered with chips are even numbers. Numbers without chips are odd numbers (see fig 18). Point out that all numbers that end in 2, 4, 6, 8, and 0 are even numbers; those ending in 1, 3, 5, 7, and 9 are odd numbers. You can then clear the board and select numbers at random, highlight them with a viewer, and ask whether or not that number is odd or even. Remember! Even numbers have a Blue 2. Odd numbers have no Blue 2. An additional exercise is to color in all blocks containing Blue 2s on the Wonder Number Worksheet. The second comparison involves determining greater than and less than, using a different number of chips. Start with 5 and 8. Place five chips on the top row of the board on the first five blocks. Then place eight chips on the second row on the first eight blocks. Next count each set of chips and ask which has more (see fig 19). To reinforce greater than and less than, stack the chips and place them next to each other. Then ask which stack has more chips. Two facts are true from this comparison. The first is that 8 is greater than 5 (8 > 5), and the second is that 5 is less than 8 (5 < 8). Give a second example using the numbers 7 and 10 employing the same procedure. You can display multiple examples with whatever numbers you choose. The third comparison features a way to understand place value through chip trading. Begin by counting out ten red chips and placing them on numbers 1 to 10 on the board. Now stack all ten red chips on the number 10. Then trade the ten red chips for one blue chip and place it on 10. The blue chip represents one set of ten. Repeat this sequence, continuing up to 20. At this point, it is important to show that sets of one are counted out horizontally across the board, and sets of ten are counted vertically down the board. Take a viewer and place it on 43. Beginning at block 1, count out three ones by placing a red chip on numbers 1, 2, and 3. These chips represent the three sets of one in the number 43. Then beginning with 13, count out four blue chips and place them on 13, 23, 33, and 43. These chips represent the four sets of ten in 43 (see fig 20). Remember! Each row down equals 10. Give another example using the number 56 and follow the same procedure. Then let the student pick a number and reach it following the same sequence.

