Initiating the Excursion
Young students' experiences with puzzles provide a background for undertaking this activity. Because similar puzzles are available for use with plastic or paper Tangrams, students could move back and forth between concrete materials and the computer environment. To facilitate this, you could have each student cut out the Tangram pieces from the second page of the Slide, Flip, Turn activity sheet. Then, before going online, place a triangle, square, and parallelogram on an overhead projector. Ask student volunteers to demonstrate the three transformations that will be used in this activity (flips, turns, and slides) as preparation for solving the Tangram puzzles. Engage students in a brief discussion about each of the three transformations. Discuss the effect that each of these transformations has on the shapes.