Lesson 7

The purpose of this warm-up is to elicit student knowledge about composing and decomposing composite shapes, which will be useful when students build their own composite shapes later in this lesson. While students may notice and wonder many things about this image, the idea that shapes, such as hexagons, can be composed and decomposed into other shapes—such as multiple triangles, rhombuses, trapezoids, or a combination of triangles, rhombuses, or trapezoids—is the important discussion point. Students may refer to the pattern blocks by their colors when describing them or sharing different combinations that may form the same shape. Use this as an opportunity to ask the students if they know the names of the shapes and review shape vocabulary.

• Groups of 2
• Display the image.
• “What do you notice? What do you wonder?”
• 1 minute: quiet think time

• “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Share and record responses.

• “Some of you noticed that the image at the bottom looks like the one at the top, but they used different shapes to make up the hexagons.”
• “What other ways could you make a hexagon with the pattern blocks?” (2 trapezoids, 1 trapezoid and 3 triangles, 2 rhombuses and 2 triangles)
• "What other ways could you make a rhombus? a trapezoid?”

The purpose of this activity is for students to compose two-dimensional shapes into larger shapes in different ways. As students work, consider asking them to identify the shapes they are using and their attributes. During this activity, the teacher may consider taking photos of the way students composed the large triangle (third problem) and the large rectangle (fourth problem) to share during the synthesis so that students do not need to move their pattern blocks to share with the class.

• Consider making the Flat Shapes Puzzles blackline master into a packet for each student. 

• Give students pattern blocks and the flat shape puzzles.

• “Use the pattern blocks to fill the outline in different ways. Each time, record how you filled in the shape with pictures, numbers, or words.”
• 8 minutes: independent work time
• Monitor for different ways that students filled in the large triangle and large rectangle puzzles.

• Display work from two students for the large triangle.
• “How was the triangle created differently? Why do both ways work?” (One way used all triangles, the other used some triangles and a trapezoid. They both work because a trapezoid is the same shape as three triangles put together.)
• Display student work for the large rectangle.
• “Did anyone find a different way to build this shape? Why didn’t we find any other ways?” (The rectangle has square corners and the square is the only pattern block that also has square corners.)

The purpose of this activity is for students to compose two-dimensional shapes into composite shapes and find other smaller shapes that can make the same composite shape. Students use pattern blocks to compose a new shape, then recreate the new shape using smaller shapes. 

• Give students pattern blocks.
• “What kinds of shapes can you make from pattern blocks?” (triangles, rectangles, flowers)
• 30 seconds: quiet think time
• Share responses.

• “Use the pattern blocks to build something new. You can build whatever you want. After you build your new object, trace it and count the number of pattern blocks you used. Then build the same object using different pattern blocks, and record how many blocks you used.”
• 6 minutes: independent work time
• Monitor for 2–3 students to share their two shapes.

• Invite previously identified students to share.
• “What do you notice about the shapes they built?” (They made a rocket. They used six triangles to make a hexagon in their first shape but used hexagons in the second shape.)
• Repeat as time allows.

The purpose of this activity is for students to learn stage 3 of the Picture Books center introduced in kindergarten. Students look through picture books and notice and describe shapes they see in the pictures. Students record the shapes they see with drawings or words.

• Each group of 2 needs at least one picture book that shows a variety of shapes throughout the book.

• Groups of 2
• Give each group two recording sheets and access to picture books. 
• “We are going to look for shapes in picture books. Talk to your partner about the shapes you see. Describe the shapes and name them if you can. Then record the shapes you see with a drawing or words.”

• 10 minutes: partner work time

• Display a page from a picture book with lots of recognizable shapes. 
• “What shapes do you see on this page?” (The sun looks like a circle. The blanket is a rectangle. The ball is a sphere.)