Mental math skills are integral to our daily lives and as such we should be teaching them to our students. Knowing their doubles facts is a key component in being able to use a variety of mental math strategies such as doubles plus or minus one, two, or three. If you have never used the doubles strategy before and aren't sure of how it can help students, consider this: "I know that 10 + 12 = 22, because I know that 10 + 10 = 20 so I just add on 2 more". Before children can learn the doubles mental math strategies, however, they need to master their doubles facts. Read on for some fun activities for teaching the doubles facts and mental math strategies.
To help students master their basic doubles facts I created these posters to display in the room. Before I hang them on our math wall I introduce the concept of doubles by bringing some concrete examples of things that come in pairs or other doubles. This past year I brought in a pair of shoes, an empty carton of eggs, a pair of socks, chop sticks, and a toy car. I set them on the floor in our circle and asked the students what they saw in common with the items. They didn't catch on right away so I did some prompting: "Look at this egg carton, how many eggs can you hold on one side? And the other side? Oh, you noticed that it's the same on each side? Now look at this toy car, do you notice anything about it that is similar to the egg carton?" And from there the students ran with it.
We decided to make a chart of all the things that we could think of that came in pairs or other doubles. Then I brought out the posters. I showed them each poster but I covered up the math fact that went with each one. When I held up the first poster I said, "What math problem do you see in this picture?" I gave them a minute to think about it, but most didn't need that long. After the first poster they all caught on very quickly and were able to see the math in each image. The only one they had some trouble with was the truck double (it's an 18 wheeler) and that was due to a lack of schema.
Watch this video for some great tips and tricks for introducing doubles:
Once the topic has been thoroughly introduced I like to reinforce the doubles facts by playing a couple of games.
This game is called, "I have, who has". You can use this game for many math concepts but I particularly like it for teaching doubles. Someone starts with 1 + 1 and they read their card, "I have the eyes double, 1 + 1 = 2. Who has the dog double?" Then the person with the dog double chimes in and reads their card. They can play this in a larger group or a smaller group but it works best with at least a group of 3.
And this is an oldie but a goodie, BINGO.
Throughout the week (and the rest of the year at random) I will also do on the fly quizzes where I call out a doubles fact at random and students put up their hand to answer. I often do this when we are lining up to go somewhere which serves a dual purpose, 1) It reinforces the doubles facts and 2) it gets them focussed in line.
Once I feel they have mastered their doubles facts I have them complete this booklet so they can take it home and practice there.
You can check out these resources by clicking here or any of the above images.
Stay tuned! My next post will be about how students can use their doubles facts to further improve their mental math skills