### Mirror Images

Standard Met: CCSS.Math.Content.4.G.A.3

What You Need: Pattern blocks, rulers

What to Do: Christy Whitehair uses manipulatives to explore the concept of symmetry. “I try to utilize the CRA model [concrete, representational, abstract] as much as possible when introducing and practicing concepts,” says the fourth-grade teacher from Garfield Elementary in Abilene, Kansas. To explain symmetry in a concrete manner to her special education students, Whitehair gives each one pattern blocks and a ruler to act as a line of symmetry. She tasks students with making a symmetrical image with the blocks.

Whitehair uses the activity with on-level students as well. They make an object without the ruler and later prove the line of symmetry by placing a ruler on top of the blocks. For an added challenge, students can create images with multiple lines of symmetry.

### Move With Math

Standards Met: CCSS.Math.Content.4.G.A.1; 4.G.A.2; 5.G.B.4

What You Need: Sewing elastic or Chinese jump ropes

What to Do: Fifth-grade teacher Kelly Hall incorporates kinesthetic activities into her geometry lessons at Whitcomb School in Marlborough, Massachusetts. To review polygons and geometry terms, she breaks students into groups of five or six. She gives each group sewing elastic knotted into Chinese jump ropes. (One package of elastic typically makes one jump rope.) Students
loop the elastic around their bodies. “I call out geometry terms, and the groups create the shape or term,” Hall explains. For example, she might ask students to create a shape with only one set of parallel sides or a shape with four right angles that is not a square. “We combine groups and elastics to show terms like intersecting, parallel, and perpendicular,” Hall says.

### Smart Art

Standards Met: CCSS.Math.Content.4.G.A.2; 5.G.B.4

What You Need: Paper, pencils, rulers, markers

What to Do: Jennifer Runde, a fifth- and sixth-grade teacher at Echo Bay Central Public School in Ontario, integrates art into her geometry lessons. To review polygons, Runde has students draw a grid on a sheet of paper, first in pencil, then in marker. (Use graph paper, if available.) Next, she has students draw a minimum of six polygons on the grid, making sure the shapes don’t overlap. As they work, students can name the polygons and note any parallel or perpendicular lines in the shapes with partners.

Students should color in the grid by alternating one white square with one filled in with a color of their choice. “I had them do all of the squares for the grid first. Then they had to go back and fill in the shapes, opposite to the pattern they did for the grid,” Runde says. The finished products can make for an eye-catching bulletin board.

### Geometry All Around

Standards Met: CCSS.Math.Content.4.G.A.2; 5.G.B.4

What You Need: Haiku Deck app (free with in-app purchases)

What to Do: Jon Samuelson, an educational technologist from Portland, Oregon, has used the presentation app Haiku Deck with fourth graders to review geometry terms for a test. First, the class made sample slides together. For instance, on one slide, they used a photo of railroad tracks and added the title parallel lines. Next, they wrote the definition: “lines that will never intersect.”

After scaffolding this activity, Samuelson allowed students to take pictures of all the geometry around them at school. Students then individually created their own slides and presentations. Samuelson calls Haiku Deck “a valuable presentation tool”—and it sure beats traditional flash cards!

### Room at the Table

Standard Met: CCSS.Math.Content.4.G.A.1

What You Need: Spaghetti and Meatballs for All!, by Marilyn Burns; sticky notes

What to Do: Teacher (and Scholastic Teachers blogger) Genia Connell, from Troy, Michigan, shares the picture book Spaghetti and Meatballs for All! to teach perimeter. In the story, Mrs. Comfort makes a seating plan for 32 dinner guests. When the guests arrive, however, they rearrange the tables to their liking. Connell tells students to set up the tables so everyone is happy. She gives students eight square “tables” (large sticky notes) and 32 “chairs” (small sticky notes). Students place the smaller squares around the perimeter of the tables to try to please all 32 guests. “Exasperation gives way to delight when they realize the only way to get 32 -places at the table is to use Mrs. Comfort’s original plan,” Connell says.