Modeling - Hard Subtraction 1
Trixie was 2 years
and 11 months at the time that this video was made.
The Problem
Trixie is playing with a collection of toy Sesame Street characters.
She has 5 Cookie Monsters and 3 Big Birds. She knows that she has more
Cookie
Monsters than Big Birds. Then I ask her, "how many more?"
What To Look For In This Video
- Trixie's ability to count even small collections of objects is very unstable. At times she has no problem whatsoever - but not here. Nevertheless, that is no reason not to introduce word problems. This may be her first exposure to Hard Subtraction 1.
- She has no problem with the question, "Are there more Cookies or more Big Birds?"
- On the other hand, Trixie seems to think that to find "how many more" she should count all the Cookie Monsters, not just the extra ones. (This is a pretty typical misunderstanding.) So I show her what the question means by explicitly showing her 1) how to manipulate the toys and 2) what to then count.