Last Friday, we assessed our 2nd graders in math word problems. Our California state standard reads...
Algebra and Functions 1.2 Relate problem situations to number sentences involving addition and subtraction.
In other words, our students get problems like, "I have 328 marbles. I find some more. Now I have 568 marbles. What number sentence can be used to find how many marbles I found?" Well let me tell you that year after year this has been a super hard standard to teach, up to now. Right before Thanksgiving, we had a great math pd on CGI (Cognitive Guided Instruction) that pretty much changed my instruction for the best. Last Thursday (a day before the test) I decided to teach word problems using the CGI method and WOW! What a difference!!! A good 80% of my students were able to create the number sentence they were being asked for! I was so happy and proud of my little ones because they really tried their best to create the number sentences. This by far, has been the best way to teach problem solving. It was fun, challenging, and motivating for us all. I thought I share the reference chart we used to explain the types of word problems.
|+/- Types of Word Problems|
A few things..."Join" means to add and "Separate" means to subtract. I actually did a lot of hand movements for these two words so that my little friends could understand that "join"meant to add and "separate" to subtract. Under the unknown column, I listed 3 different types of problems.
*Result unknown: You don't know the answer and you are trying to figure this out. (ex. I have 5 apples and I get 2 more, how many do I have? OR I have 8 apples, I eat 3, how many do I have?)
*Change unknown: This means that you are searching for the number that will change what you
started with and will give you the result. (Eric has 72 golf balls. He finds some more in the basement. Now Eric has 183 golf balls. How many golf balls did Eric find in the basement? OR Kristin had 17 apples. How many more apples will she need to have 39 apples all together?)
*Start unknown: You don't know what number you start with (ex. Clifford has some bones. Emily gave him 23 more bones. Now Clifford has 46 bones. How many bones did Clifford have to start with?)
Let me know if you have any questions regarding this strategy or if you decide to try it out. Like I said, I loved teaching it last Thursday and my students really understood what they were doing. Okay, that's all for now. Live, love, and laugh in your classrooms! :)