Seventh graders explore what happens to a hot air balloon when they add or remove units of weight or heat. This activity is an informal exploration of addition and subtraction with positive and negative integers.

Students who have a clear understanding of the previous lessons can work on gallery problems of their choosing. This can be used as a good review or assessment.

Students reflect on their work and apply what they've learned about the characteristics of geometric figures. Includes a learning game to be played with a partner.