Teacher monitors learning through effective assessment – Example 12

I understand now. So the missing number is 4,504. Now you understand me? Wow, what went on over here? I see that you guys have three parts up here. Why? Bradley, why? Because Susan had 1,123 trading cards. Lucy had 1,349, and we don’t know how many Becky has, but we know all together they have 6,976. So how did you go about solving for that missing part? So I totaled both of them.

Right. I said I got that number. First we added those two numbers to get that number. And then I subtracted that from that number, and I got 4,504, and then I added 4,504 plus 2,472 and I got the number. I have a question. Why in the world would Jack have combined this number and this number together before he subtracted from this? Teagan, why do you think he combined this and this before he subtracted? Because it gives you part of the whole, because like you have to add them all together. Exactly. Which really is the whole. Right, but you wanted to add both. You can. You can combine your parts together before you subtract. Some kids though, sometimes would do 6,976 and minus that and then do that. At first Jack wanted to do that, then I suggested to add those two together.

And did you understand Bradley’s deduction? Okay, so come up with a way to check your answer. .