Adding 3 Whole Numbers

For those who don't know me....I LOVE MATH!!!! It is sort of funny because I disliked it so much when I was in school, but now I could teach it all day!

So this week in math we have been learning all about adding 3 whole numbers. We started by using manipulatives to help us add and have gradually taken away the manipulatives and worked our way to mental math. Keep in mind, we have been doing addition and subtraction concepts for WEEKS now.

Initially I presented my students with the question, "How do we use objects/manipulatives to help us add 3 numbers together?" The students have had numerous experiences with manipulatives and problem solving throughout the year. (*more on problem of the day to come later). We brainstormed a list of possible manipulatives we could use to solve a problem asking us to add three whole numbers. The list included the usual: cubes, base ten blocks, counters, etc. But they also came up with other ideas which were interesting to me...money, crayons, and scissors (they really got stuck on the idea of scissors, but I told them to go ahead and try it). I presented the students with the problem 6 + 6 + 2 and asked them to go to their seats and use whatever object they wanted to use and solve it.

I walked around and helped the students through their thinking process. I was really curious as to who would see the double and add that first. I wanted to know how they were counting. Were they counting one by one? Counting on from 6? Counting on from 12? Or using another method?

We then returned to the carpet to discuss our thinking. I find this to be the MOST critical part in mathematics. Discussion! It is AMAZING what these little ones can come up with and the way they manipulate the numbers. Here are some examples of what they did...

As you can see many of them just modeled the numbers as expected. However, the explanations is really were the "meat" of the lesson was. I really loved the one above who broke the sixes into its double (3+3). I thought it was unique. I also had some experiment with money, but they decided it wasn't really conducive to the problem. Some of the students also did base ten blocks, but I did not get a picture of it. :( I will get better the more I blog (I hope!).

We then went into our guided math groups and the students did their problem of the day (which was adding 3 whole numbers, of course!), workbook page, math tub games, and we met and completed this activity.

The students had to roll a dice 3 times and record their numbers. Then they used a manipulative to add them together and solved the problem. They seem to love any game that involves dice/number cubes. The next day we still focused on adding 3 whole numbers, but our focus was how do we draw a picture to help us add. Today we focused on how we could do it mentally in our heads by looking for doubles and tens to add quickly. More on that to come. 

In a side note:

2 more days until SPRING BREAK!!!