Monday, March 15, 2010

Homeschool Conversations-Pt.3

We are working our way through Singapore's Challenging Word Problems 1. We just got to the section on multiplication. We haven't worked on multiplication since we covered it in Primary Math 1B which was around Christmas.

So here's how two of our problems went this morning:

D-Man: That's 9x2. I have to go potty. Be right back.

D-Man: (Immediately after the quick trip to the restroom) That's 18.

Mom: That was fast, how did you know that?

D-Man: Well, I was thinking about it while I was going potty. 5-2's is 10 and another 4-2's is 8. 10 plus 8 is 18. It's really just an adding problem.

Mom: Wow, that's exactly right.

Next problem...

D-Man: (After reading the probem) That's 3x2. Hmmm...That's 10-4. It's 6.

Evidently, he thought that 5x2 = 10 and 2x2 = 4. When you subtract them, you get 3x2.

Interesting math day.

7 comments:

Dad said...

What?

This kid is gonna be dangerous. I would have never thought to do (5*2)-(2*2) = (3*2) = 6

Sarah said...

Nice, your higher education shows in your correct long written out equation. :)

Dinsfamily said...

Here I was thinking we were going to practice counting by 2's.

That math minor is certianly coming in handy teaching arithmetic ;) See, those extra classes were worth it.

michelle said...

Wow! My college students can't do that. Such reasoning is exactly what I wish all students could begin with. Then the facts are not just memorized, they truly make common sense.

mommygirl @ HCA said...

Great Job to both of you... mommy and student!

Michelle said...

I was telling my husband about this last night. We were wondering, as parents who are just beginning to homeschool our 5 yr old, how did you get to this point? Do you think it was a particular curriculum or process? Do you think it was playing? As a math teacher, I understand the depth here, and that is what I want for my son, too.

Dinsfamily said...

Michelle,
Thanks for your comments. I think it was a couple of things that got D-Man to this point. First, he's just a mathy guy. He thinks about math a lot and was often discovering math concepts (like multiplication) on his own before we started with any curriculum. Second, we've been using two concept-based curricula this year. Between Singapore and Miquon, he's gotten a good understanding of what it means to multiply 2x5. He's seen it in pictures and used manipulatives to demonstrate what's going on in the problem. At his age, I'm more interested in him understanding the relationships between addition, subtraction, and multiplication than just memorizing facts. He does know his addition facts well and we're working on cementing his subtraction facts, but haven't started on multiplication tables yet. Third, this really suprised me. I'm learning that we don't have to teach them everything, but give them opportunities to figure things out. That's why I love Miquon math right now. I'm going to write a post on it today or tomorrow to explain what it is. I hope that helps. --Taira