Ages: 5 and up
Math Ideas: Counting, comparison
Here's a quick one: Think of a number. Don't tell me what it is, just keep it in your mind. Alright?
I've got one too. When I say go, let's both shout out our numbers. Ready?
Ok, now think of a number that's between both of those numbers. I'll do the same. Ready to shout it out?
How to Play
I went on a trip with my son this past week, so I invented this game for those moments when even the iPad couldn't hold his attention any longer.
The goal of the Between Game is simple: yell out the same number at the same time. The only constraint is that you must each choose a number that is between the two previous numbers. That way, the range of numbers shrinks and shrinks until both players think of the same number.
To make the game last longer, you can try to play until you say the same number after three or two rounds. It's tough, but it happens. Once, my son and I both yelled out "100!" on the first round to our mutual delight.
Where's the Math?
The Between Game is a fun way for kids of all ages to pass the time on long car rides, but the game is a significant learning experience for kids ages 4-6, who are still learning how to compare numbers.
My daughter, who is 3, can count into the 20s, but if you ask her "What number comes after 5?" she will randomly guess a number (and sometimes a letter!). She knows how to count, but she doesn't yet know how to compare.
My son has a stronger sense of the number system, but it still takes him ten or so seconds to settle on a number between 65 and 73. Even then, he still gets tripped up. If I switch the order of the numbers and ask him to think of a number between 73 and 65, he is just as likely to say 80 as 70.
Playing the Between Game gets kids thinking about the magnitude of numbers in a new way, while remaining accessible to kids who are still learning the number system.
Questions to Ask
If you play a few rounds, you and your child will eventually say adjacent whole numbers, like 15 and 16. A great question to ask here is "Are there any numbers between 15 and 16?"
Young kids aren't yet ready for a formal introduction to fractions and decimals, but they are certainly familiar with halves. If they need convincing, you can always talk about ages. Any kid who is older than four has been proudly 3 1/2.
If your child seems very confident with the numbers from 1 to 20, you can start dragging the game into higher numbers. Or you could get cute and start with "four billion!" just to see what your kid says next.