Yesterday’s subtraction number talk was very revealing….we had some of the students who have a lot of addition strategies using their fingers. So today’s number talk was subtraction again. BOY did it produce some interesting discussion. We had 3 different answers and lots of logic being discussed:
“I came up with that answer too the first time but I KNEW that 5 was too small so I went back to look at it again”
To me this was one of the best statements I heard today. I had students jumping out of their seats to share their strategy about A SUBTRACTION PROBLEM!! It scares me because some (high school) students didn’t see how 5 could be unreasonable but I am also glad that we are having this discussion at all. What if they weren’t exposed to it AT ALL! That would scare me even more….Better late than never!