I. Teacher Information:

Title of Lesson: Tangrams and Mammals

Topic: Math Process: reasoning

Math Product: geometric properties

Science Process: classifying and constructing models

Science Product: tangram mammals

Student Level: 4th-12th grade

Objectives:

1. The students will construct the tangram pieces from a square paper by following directions to fold and cut.

1. The students will make observations on the pieces formed and compare how they are related to each other.
2. The students will explore patterns and shapes with the tangram pieces by constructing mammals.

Materials: 32 square sheets of paper, 32 scissors, example papers for the instructors, 32 sheets for the students with list of animals, 32 sheets for the students to write observations and define helpful terms, construction paper, glue, and Grandfather Tang's Stories.

Prerequisite Skills: The students should have basic knowledge of and be able to identify triangles, squares, trapezoids, and parallelograms. Students should also have knowledge over mammals.

Time Required: 45 minutes

• The time will vary by how much the students know of the shapes being made and how much the teacher will have to review material.

II. Teaching Procedures

Introduction:

Explain what a tangram is (seven geometric shapes that come from a square). Show an example. Explain that they will be making the seven tangram pieces today in class.

Review: Remind the students of the different shapes they should be looking for while constructing tangram pieces. Review the definition of parallelogram and trapezoid.

Strategies

1. Students will fold and cut a square piece of paper by following the directions listed below. Students should discuss and record observations in small groups after each step.
2. Pass out the square paper, scissors, and sheets to record observations to each student.
3. Divide the students into groups of three. Explain for each group to assign a recorder to write the observations and discussion down. Make it clear that the observation sheet is to be done in groups, but the actual making of the tangram is done individually.
4. Give directions for making the tangram pieces:

   a. Fold the square sheet in half along a diagonal, unfold and cut along the crease. What observations can you make about the two pieces you have? How can you "prove" that your observations are correct?

   b. Take one of the halves, fold it in half and cut along the crease. Make more observations and be able to support your statements. Define midpoint, vertex, and right angle.

   c. Take the remaining half and lightly crease to find the midpoint of the longest side. Fold so the vertex of the right angle touches that midpoint and cut along the crease. Continue with observations. Define congruent and similar triangles as well as trapezoid.

   d. Take the trapezoid, fold it in half and cut. What shapes are formed? Students may not realize that these shapes are trapezoids as well. What relationships do the pieces cut have? Define acute and adjacent.

   e. Fold the acute base angle of one of the trapezoids to the adjacent right base angle and cut on the crease. What shapes are formed? How are these pieces related to the other pieces? Define obtuse angle.

   1. Fold the right base angle of one of the trapezoids to the opposite obtuse angle. Cut on the crease. You now should have the seven tangram pieces.
5. Review the tangram pieces: What shapes have been made? Are there any congruent and/or similar shapes?
6. Explain the mammal project: Students will identify a mammal from the list of animals and construct the mammal from their tangram pieces. The tangram pieces should be glued onto a piece of construction paper, and the mammal constructed should be labeled.

- show pictures of the tangram mammals

• pass out construction paper and animal list to each student
• pass out scissors and glue

7. Decorate the tangram mammals if time allows.

Conclusion: Share the tangram mammals and what makes the animal a mammal.

Evaluation: (the teachers will complete a check list for each student while they are constructing the tangram mammals.)

1. Check to see if each student has seven tangram pieces.

1. Collect observation sheets and tangram mammals.

III. Extensions:

1. Have the students reassemble the seven tangram pieces into a square.

2. Display tangram mammals on a bulletin board or around the room.

3. Have students determine the measure of angles formed in the different tangram pieces.

Resources: Ask Eric Lesson Plans: Tangrams

http://ericir.syr.edu/plweb-cgi/fastweb?getdoc+lessons+lessons+