She wanted the kids to understand what was actually going on with the numbers, so we spent most of last week talking about scientific notation and what it really means to multiply by 10.
Using exclamation points as units, here's 1:
!
Here's 10:
!!!!!!!!!!
And here's 100:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Each time we multiply by 10, we really get a lot more stuff!
Scientific notation uses these facts:
10^0=1
10^1=10
10^2=100
10^(-1)=.1
10^(-2)=.01
With scientific notation, instead of writing a distance as
320 meters
we would write it as
3.2 x 10^2 meters.
This helps us get a sense of how big (or small) things really are, in relation to distances we have some sort of feel for. 2 meters is relatively easy to think about. 20 meters might be a little harder to think about - but 20 meters is really 2 x 10^1 meters, which is 2 meters repeated 10 times.
We had a great time measuring out our own scale of the universe on the sidewalk, and filling in things like the length of our math class (with and without teachers).
Here's Stanley writing the scientific notation:
10^(-1) and 10^(-2) are pretty small!
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