Tuesday October 21st

Hello students & families!

I haven't posted for a few days because I feel like we have been doing really well with our multiplication problems we have been working on. 

Today, we are introducing multiplication with decimals. 

One number 1a. I first start by estimating the product. I round 53 to 50 and 1.2 to 1. I then multiply 50 x 1 which equals 50. This tells me that my answer is going to be around 50. 

Now, I draw my area model and decompose (break up) my numbers. I change 53 to 50 and 3 (if added together would equal 53). I change 1.2 to 10 tenths and 2 tenths (if the kids plugged these numbers into their place value chart, they could see that 1 is the same as 10 tenths). 

Now multiply 3 x 10, 3 x 2, 50 x 10 and 50 x 2. 

Now I add up each row. Then add the two rows together to get 636 tenths, which is the same as 63.6.

On the right hand side of the paper, we use the standard algorithm. As you can see by my arrows, I can easily match up the numbers as I am working the problem. This tells me that I am doing it correctly. 

*Spelling test Friday! 

*Half-day Friday!

Thanks,
Mrs. C