Listen to this song
Taking imaginary numbers and shaking them has been a fun, successful way to teach my children to quickly add two numbers. When we have a problem, such as 9+3, the class grabs an imaginary 9 in the air. We shake together. Then, on our fingers, we add 10, 11, 12. You can also use this technique when adding on to large numbers for such problems as 42+4.
Many teachers hesitate to let children use their fingers. In a problem like 6+2, children will often put up 6 fingers, then put up 2, and then count the total. This song allows children at this stage to skip the 6 part! While we should work with children to quickly recall facts, let’s remember that throughout children’s math lives, to calculus and beyond, they will be using real objects and drawing pictures to understand concepts. Our fingers are just one more tool.