The Problem Solving and Communication Activity Series Work Backwards

Work Backwards

When "work backwards" applies to a problem, it's a really powerful strategy. The key is to ask, "what must have happened right before that?" We offer students techniques for visualizing problems, and then visualizing them backwards.

We also offer some ideas for those tricky problems where you know what's given and what you're trying to get, but you don't know the steps in between. Working backwards can help in those situations as well.

Activities to Learn this Strategy

Facilitation Questions

  • What's happening?
  • What must have happened before that?

Recommended Problems

The Strategy Examples documents linked from these problems contain examples of what students could do with the activities. You need a Class Membership or higher to access Library problems.


Charlie's Gumballs

Math Fundamentals

Fish in a Barrel
Chicken Little's Eggs


Eight Squares on a Table
Mixing Marbles


Lettuce for Sale
Swapping Marbles


Off on a Tangent
Snail's Trail

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