Choose a picture and use all seven pieces to fill in the outline. To choose a picture, click on a tangram puzzle from the choices at the bottom.

To move a tangram piece, click on the piece and drag it to the desired location. To rotate a piece, drag it by a vertex. To select a tangram piece, click on it. To color a selected piece, click on a colored button on the right. Other features can be accessed from the following buttons:

	Flips the tangram piece that is selected
	Resets the work space
	Shows an outline of the solution

Getting Started

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 can move back and forth between concrete materials and the computer environment. After the students have had time to work with the outlines, teachers might ask them questions such as the following, which challenge them to try different solutions or to reflect on the strategies they used to solve the puzzles:

• Can you fill the outlines in another way?
• How many different ways are there to fill in this shape?
• What do you do when you cannot figure out a puzzle?
• Can some tangram pieces substitute for others?

What Students Learn

Whereas completing the same or similar puzzles with both physical and computer manipulatives may help students generalize their experiences, the computer environment is likely to encourage them to think about how they need to manipulate the tangram pieces rather than approach the task mainly by trial and error. Working with a partner at the computer to complete puzzles also encourages students to become more precise in their use of vocabulary about space. Teachers can enrich students' vocabulary in class discussions by these comments on students' actions, such as "I see you are rotating the parallelogram " or "What difference would flipping make?"

Take Time to Reflect