Teacher Notes
X
Build a stack of five connecting cubes and a stack of eight
connecting cubes to display for students. Read and discuss each
question. Emphasize that 8 is three more than 5 and 5 is three
less than 8. Point out that if you add three cubes to five cubes,
there will be eight cubes, and if you take away three cubes from
eight cubes, there will be five cubes. Encourage students to use
their desk number lines to model three more and three less.
Repeat with one or two other combinations where one stack
has three more cubes than the other.
O. Three More and Three Less 
Here is a stack of five cubes. Here is another stack of eight cubes.
- How many cubes should we add to the stack of five cubes
to make both stacks the same?
- How many cubes should we take away from the stack of
eight cubes to make both stacks the same?
