Get Yo Math On! {Addition & Subtraction Strategies}



It's rodeo season in Houston so, .... howdy yaaaaa'lllllll! But, let's not talk rodeo just yet, let's talk MATH. My class has been learning and practicing new addition and subtraction strategies. By new, I mean NOT drawing pictures, using our fingers, or counting forward or backwards to find the answer. Don't get me wrong, couting on our fingers still works, but it's time to introduce some new (and a bit more sophisticated) strategies.

SIDE NOTE: I try really hard to think up ways (or beg, borrow, steal, or Pin ways) to start math class with an interactive hands-on lesson. Somedays what I come up with works really, really well. And, some days I wonder what on earth was I thinking when I decided to try that!??? The conversation in my head sounds something like this, "It must be a full moon...no, maybe the barometric pressure dropped...errr...maybe we will try this a DIFFERENT way tomorrow." But to avoid embarrasing myself, I'm going to limit this post to lessons that worked :-)

This week's Humpday Highlight (with Ms. Stanford's class) is all about math strategies we have been learning.



Making Ten to Add
I used masking tape to make a ten frame on the floor and some foam circles I found in a cabinet as counters. Our goal was to take an addition problem and make it start with 10, because adding anything to 10 is super fast and easy!




After the students assisted me with the floor demo, they each got a baggie of counters and a ten frame, so we could all practice at the same time. 



My firsties thought making ten was fun, and almost everybody caught on quickly. 


Number Bonds and Fact Families
We used one full size hula hoop and two mini hula hoops (Dollar Tree, baby!) to create human number bonds and human fact families. I gave three students foam discs with numbers written on them. The kiddos stood in the hoops to make a number bond. Next, I gave two more students a +/- sign and an = sign. The students in the hoops joined the other two students to create a number sentence. Finally, a volunteer student played "director" and told the students that were holding the numbers how to rearrange themselves to make three other number sentences that were part of the same fact family. 




Related facts (Using an addition fact to solve a subtraction problem.)

I made a tic-tac-toe board using white butcher paper. Inside the squares I wrote two subtraction facts in the same fact family. The class split into two teams and sat together around the board. A player rolled two large dice and then stated an addtion fact that could be made with the two numbers on the dice, "I rolled a six and a three. Six plus three equals nine."  Then I asked, "Do you see a subraction fact on the board that is part of the same fact family as 6+3=9?" If there was a related fact (like 9-6=3), then the student got to cover it with a foam dot (pink for the girl team, blue for the boy team) after he/she read the facts out loud. If a related fact could not be found, then the team lost its turn.




First team to get three in a row wins.

Tomorrow, we will take it a step further and explain HOW an addition fact can help solve a related subtration problem. I wrote related facts on cookie and milk bulletin board decor (Dollar Tree for the win!) so partners can turn and talk about a pair of related facts with each other. Then, we will play a matching game (like Memory). If a student flips over two related facts, he/she will explain how the addition fact helps find the answer to the subtraction probem. Give an explanation and the correct answer to earn a point for your team.


Happy strategizing! 

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