Students explore effective mental strategies for performing subtractions. Strategies include: 'round to the nearest 10', 'subtract tens then ones', 'subtract ones then tens' and the 'compensate' strategy.
Teacher notes
- A partitioning model is shown so students can see the effect of breaking up numbers to solve a problem using known facts.
- The strategies are available through an animation that appears on the launch of the learning objects and are also available as 'hints' while students work.
- The printouts show how the student solved each equation.
Learning objects
The take-away bar: generate easy subtractions | |
The take-away bar: make your own easy subtractions | |
The take-away bar: generate hard subtractions | |
The take-away bar: make your own hard subtractions | |
The take-away bar: go figure | |
Take-away bars |