Johnny is in first grade and, according to his teacher, he should already know how to count by fives. And he can do it. . . sort of. He gets the basic idea, but when he skip-counts to 100, he almost always leaves out a few numbers.
When I would suggest that he practice this skill, he used to object with vigor. But today, we found a way to make it fun. I'd go so far as to say that practicing counting by fives at our house is now a rip-roaring good time.
First, let me clarify that Johnny already understood the concept of counting by fives. To make sure that his conceptual understanding was solid, we looked at a number line that I had drawn. I had written in the multiples of ten (i.e. 10, 20, 30, etc.) and drew dots for the numbers ending in five.
Johnny had to think for a moment before he figured out which numbers belonged on the dots. (His first response was that the dot between 10 and 20 would correspond to 11. After he realized that it would actually be 15, we had a fun time figuring out where 11 would actually go.)
But skip-counting by fives is something that I wanted Johnny to be able to do effortlessly and without referring to a number line. He needed practice. And we needed the practice to feel like play.
So we invented . . . Silly Skip-Counting.
Since Johnny's most common mistake was going straight from 35 to 50, our first version of the game was to count by fives to 100 in the usual way, except that when we came to the number 40, we said it in the silliest way possible. The possibilities were endless: Wail 40 like a siren, make a silly face and waggle your fingers, roar it like a lion. And he never forgot to say 40 because he didn't want to miss out on the fun.
Then we were ready for something more challenging. We each took turns giving special instructions for two of the numbers. "You have to scratch like a monkey when you say 35 and run around the room when you say 80." Or, "You have to pretend to blow on a trumpet when you say 15 and wave your arms and cheer when you say 50." (We usually demonstrated for the other person.)
Once, when Johnny's challenge for me involved doing something hilarious (I don't remember what) at the number 40, I purposely skipped that number. This was a number that he had forgotten in the past, so I wanted to see if he would notice the omission. He did indeed notice, laughed delightedly at my subterfuge, and made me go back and count again.
When my husband Owen came home from work, he was enlisted in the game. Johnny and I teamed up together to think of a really good challenge, but Owen one-upped us. When he got to 80, instead of just scratching his armpit as he had been instructed to do, he stood on a chair, touched the ceiling with one hand, and scratched his armpit with the other hand. Hilarity ensued.
. . .
I'm hoping that this approach will help with other sequences that Johnny may need to memorize in the future (e.g. days of the week, our phone number).