[jakelily]

Does anyone have any good subtraction ideas for an observation?

[mmmejias]

I did a Math Observation last year and I read a book from Stuart J. Murphy. He is awesome. His books all relate to a math lesson. Then I created a felt board activity.

He loved it!!!

[patioprincess]

I did my observation on "domino addition." You can do the same thing with subtr. You could show some big dominoes. Discuss how addition allows you to take 2 parts to make one whole but with subtraction you start with the whole and take one part away. Do lots of examples together. Then divide into partners. Give each group a bag of dominoes (5 or 6). Each student could write a subtraction problem. 10-4= 6 and then 10-6=4 You can make it higher level by having the kids write addition problems too 4+6= 10 and 6+4 = 10.
For assessment, give them a worksheet with dominoes for them to write problems. I also gave them rectanges and had them make a domino and then write the problem on the back. You can use these as flashcards later. Good luck with whatever you do. You'll do great!

[1stteacher1st]

I'm not sure how far along you are with subtraction but you could start with the story "Ten Little Monkeys" which counts backwards from 10 and relate it to subtraction. Supply students with workmats (beds) and counters (monkeys/counters) and act out the story using various subtraction story problems. Have the students write the subtraction sentence on another paper to show their understanding of the problem.

You could add a challenge component with missing addends. There were 7 monkeys on the bed and now there are only 5. How many monkeys fell off the bed?