Shortcuts - Easy Multiplication
Rose was 6 years and 7 months at the time that this video was made.
The Problem
There were 5 buses and there were 2 chickens on each bus. How many
chickens are there altogether?
What To Look For In This Video
- I think that Rose started out by counting by ones on her fingers.
I think that she was trying to keep track of how many 2's she had
counted and at the same time keep track of how many altogether.
- One, two (that's one set of 2)
- three, four (that's two sets of 2) . . .
- But when she got to her 5th finger she started to think that this method was too complicated. (She needs the fingers on both hands to represent the chickens - and a third hand to count with.)
- After a brief pause she realized that she could solve the problem by counting by 2's. In other words, she realized that the model is unnecessary.
- It is not at all clear how she knew to stop counting by 2's after 5 steps (when she got to 10). But as she counted by 2's she must have simultaneously kept track of the number of 2's that she had counted.
I think that Rose may have practiced "rote" counting by 2's - that is, just saying the number names in order without reference to any actual objects. But I doubt that anyone has ever told her that she can use that skill in connection with a word problem like this one.