- Sort and identify two-dimensional shapes by comparing number of sides, side lengths, angles and number of lines of symmetry.
- Compose and decompose two-dimensional shapes and show that the area of a shape remains constant regardless of how its parts are rearranged.

- Read aloud of Warlord’s Puzzle followed by pair or small group work.
- Students should be able to name 2D shapes and be familiar with tangrams.

- Book: “Warlord’s Puzzle” by Virginia Walton Pilegard
- Read Aloud Available – Warlord’s Puzzle: Approaching Math Through Story

- Tangram puzzles (Appendix A)
- Tangrams
- Alternatively, Tangrams can be printed out and cut for students (Appendix B)

Introduction:

- Read the story Warlord’s Puzzle to students and ask students what they know about the features of a triangle, a square and a parallelogram. Review with your students the number of sides each shape has, along with the types of angles and lines of symmetry.

Lesson:

- Provide each student or group of students with a set of Tangrams.
- In pairs or small groups, students must solve “the broken tile puzzle” by making the pieces fit into a square.
- When students have solved the puzzle, they can share their solution with a partner to compare their answers. Encourage the students to make connections about how shapes can be composed in more than one way to successfully put all seven shapes into a square.
- Bring the class back together as a whole group. Ask students to share what they recognized after comparing their answers with their classmates. Were there any differences? What were the similarities?
- To continue this activity, we have prepared additional puzzles for the students to attempt. Tell students, “Now that you’ve solved the puzzle, the King has provided more puzzles for you.” Project the additional puzzles (Appendix A) so the entire class can view them.

- How do students identify where each Tangram piece should be placed?
- Can students instantly recognize the correct position (i.e. Do they visualize whether the piece is correct before placing it in its position)?
- Are students using any positional language when deciding where to place each Tangram?

Share on facebook

Share on twitter

Share on email