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The Take-Away Bar

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 Students solve problems that take away a single-digit number from a double-digit number.
	The take-away bar: make your own easy subtractions Students create their own problems, taking away a single-digit number from a double-digit number.
	The take-away bar: generate hard subtractions Students solve problems that take away a double-digit number from a double-digit number.
	The take-away bar: make your own hard subtractions Students create their own problems, taking away a double-digit number from a double-digit number.
	The take-away bar: go figure This is a tutorial that is designed for use by the student or as a demonstration tool for the teacher. The tutorial covers various strategies for subtraction. It is amenable to a screen reader.
	Take-away bars 'Take away bars' is an aggregated learning object combining the five other learning objects.