Tuesday, March 8, 2011

Estimation & Measurement

It's been a while since we brushed up on things like perimeters and estimation, so we tackled both today. Both of which fit in quite well with our measurement study that's brewing around here.

Today, when we pulled out a couple of Math Mammoth worksheets the boys were delighted to see a "connect the dots" {better known as dot-da-dot around here} which required the use of measuring devices.

You see, we do happen to use math worksheets around here from time to time. This year I splurged and picked up the Blue Book set of Math Mammoth books from Currclick.  I didn't buy a group set because I wanted the Aussie Money and the Metric Measurement books, so I went a different route. This doesn't stop us from adding to our math notebooks, it just means I don't always need to come up with the math problems on "worksheet" days. It also means I have more resources at the ready when we're studying certain topics.

Anyway, today I was delighted to see the perimeter work problem and then there was a fun estimation problem as well. The idea was to guess how long you thought each line was and then to actually measure it and see how close you were. Morgan loves this kinda stuff, he lives for it. Jayden? Not so much. He was honestly terrified by it for fear he'd get it wrong. So, I pulled out the dried beans.

I measured off the table and told the boys how long the table was in centimetres. Then, I put a black bean on the edge and gently, oh so gently, flicked it up the table. I laid a guess as to how far I thought it had traveled. This isn't easy for me because my ability to visualise metric measurements still stinks, mostly because I still use imperial when I can. Grams and Kilos don't throw me, but centimetres and millimetres do! Then I had the boys each take a turn.

This game elicited much laughter as a few beans were flicked so hard they flung across the table and bounced off other areas of the room.  So I reminded them that the idea was to keep it on the table!  It didn't take long for them to control where they were flicking the beans which allowed them better guesses at the distance their bean had traveled. It also made measuring them a lot easier because we were only working with a typical ruler.

The activity was one I had planned for the week anyway, but originally I was going to read them Jack & The Beanstalk first and then give them each their own "magic" bean. This way worked just as well. Jayden became more much relaxed with the idea of estimation, and we also took the time to review then fun we'd had with Counting On Frank.  I think we might have an estimation jar floating around for a while to help Jayden understand that estimation is all about guessing.

1 comment:

Diana said...

What a clever idea! Love it! We haven't done much in the way of estimation, this would be a fun way to introduce it!