Today is my birthday. Griffin (12 years old) gave me three chocolate bars as a gift. He gave me candy because he is deeply aware of its value in life. He gave me dark chocolate because he knows it’s my preference.
He is frequently disturbed by how slowly I eat these gifts of candy he gives me.
Here’s how my after-work greeting went this evening.
Griffin (12 years old): Happy birthday, Dad.
Me: Thanks.
G: One thing I’ve noticed about you is that you eat the candy I give you incredibly slowly.
Me: I know. But actually I ate half of one today.
G: Half of a bar, or half of all the bars?
Me: Half of one bar. And then maybe I’ll have another half tomorrow.
G: Oh brother.
Me: And since I know 3 divided by 1/2 is 6…
G: You ate one-sixth of it.
Me: And it’ll last me 6 days.
Having arrived home a bit chilly and damp from the bike ride in the 45° rain, I went downstairs for a shower and he returned to his iPod.
So What Do We Learn?
I haven’t written a lot about this boy recently because he is in a phase of rejecting everything the adults around him care about. All adolescents go through some form of this. He is doing it with gusto.
In any case, the groundwork we’ve laid in the early years has paid off. When math is useful for his purposes, he will use it. Here, he wanted to prove his point that I am a painfully slow candy consumer. That made it important to clarify that I had not eaten half of my candy, but only half of one bar of candy.
We play around with units like this frequently. It has contributed to both children’s place value understanding, as well as their fraction work.
Starting the Conversation
Ask frequently about the units that are attached to the numbers in your lives. When you’re cooking, ask, Should we use 3 eggs or 3 dozen eggs? Ask about how many pieces of candy a pack of Whoppers is at Halloween.
Look at these pictures—one at a time—and ask How many? Challenge yourselves to find different numbers, and different units. (For example, there are 15 avocado halves, 7.5 avocados, 8 pits, 7 holes, and 1 cutting board).
