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The material consists of a presentation tray containing six colored boxes of bead material, one box containing 5 sets of colored bead stairs, one box containing 5 sets of negative bead stairs, one box containing 1 black and white bead stair, one box containing 1 red and white bead stair, one box containing 23 golden ten bars and one box containing 23 gray ten bars.

This material is used to introduce the concept of negative numbers.