Check out my newest home decor item, a hundred chart. The amount of work I put into it, I consider getting it framed to be proudly displayed in the living room. The thing is monumental in several ways:
1. It is monumentally different from my usual approach to choosing math aids. My rule is if it takes me more than 5 minutes to prepare a math manipulative, I skip it and find another way.
2. It is monumentally time-consuming to create from scratch all by yourself.
3. It is monumentally fun to show to a child.
My son, like many other kids, is fascinated with big, huge, stupendous numbers – a million, a billion, a googol. He is also comfortable with very small numbers, all the way up to 7 or 8. But the space in between, particularly the first hundred, is confusing and thus boring to him.
Some of the math tools we’ve tried so far – fingers, counting sticks, pebbles, marbles, counting bears, abacus, Cuisinaire rods, the number line, even (gasp) rote memorization… No matter what we tried, number facts for anything greater than 7 remained incomprehensible.
Getting slightly desperate, I spent several evenings making this chart. It doesn’t look exactly like the usual hundred charts. Instead, each number has bars underneath. There are bars for units and there are bars for tens and 100 has a bar for hundreds. Each bar is made up of 2 rows of 5 cells. So, the number 35 has 3 bars in the tens space and one bar in the units space. All three of the tens bars are colored in, but only 5 cells of the unit bar are colored.
The idea is not mine, but taken from an old Russian book by Nikolay Zaitsev. In it, Zaitsev explains that with a chart like this, a child gets to see exactly what each number is made of and develops an idea of place value without lengthy and confusing explanations.
We’ve just started working with this hundred chart. By this I mean we finished putting it together, looked at it, counted to 55 or so, then skip counted by 10 to 100. Oh, and my son put stickers on the most important numbers (the ages of all family members, our cat and Preston Stormer, his fave toy of the moment). Along the way, my son asked some terrific questions that never came up before:
1. Why are the numbers from the bottom repeat in all over numbers?
2. What are these bars and why not all of them are colored in? Can I help you color them in? How many do I color in for this number? Why?
3. Look, if I go this way (moving from right to left), numbers are getting smaller! And this way too! (top to bottom)
4. (Halfway through chart-making) I think you will run out of space because the cards are getting bigger. How many cards can fit on the board?
5. Why are there more bars for this number (78) than here (18)?
I gave my son a couple of left-over cards since I printed a couple of pages twice. He was busy drawing on them and coloring in the cells. Then he created his own card for the number 5 (this is how many weapons of a certain type Preston Stormer has on him):
He now stops by this hundred chart a few times each day. And the most frequently asked question nowadays seems to be when are we going to expand this chart.