Also known as the day I pissed off most of my students, on purpose.
I didn't plan to irritate them.
We did our number talk and it involved a subtraction problem with lots of regrouping. After walking around and seeing my students' answers, I noticed about half of them got the answer right. Others were having calculation issues or subtracting from left to right and getting all confused.
So I started the problem and asked what my next step was (it was regrouping). The answer I got was to add a "1" to the one's place. I asked if I was adding one or ten. I was told one. I asked where this one came from. No one could tell me.
Face palm. This does not bode well for math this year.
So we stopped solving the problem.
I gave them a two digit subtraction problem instead: 51-37. Almost all of them got it right with the algorithm. I saw one student try with a number line (yay!). Then I modeled the problem with manipulatives (rods and cubes).
I explained that when we are regrouping, I'm not adding numbers out of no where. I'm taking a set of ten from the next place value and redistributing them. I wish I had these to use to show them actually breaking apart a set of ten:
But alas, I don't.
I gave them another problem to solve, both numerically and with a picture. Most of them got it right using both ways.
Next week we'll go back to larger place values. We'll also use manipulatives because they don't have enough hands on experience with making groups. I've got some large gaps to fill!
After math, I asked them how they felt using this system:
Most of what I got in response was this:
They aren't there yet. They told me they need more practice. I told them good.
I got a lot of confused faces.
I told them that in math, they aren't going get the concept on the first day. I told them I'm going to require multiple ways of thinking about the problem. I told them they're going to have to prove they understand what is happening with the math, not just show me the right answer.
Many of my higher students are not happy with this challenge.
To them, I say good. They'll be better off in the long run. I had some grumpy math faces today!