Measurement
Comparison
Area
NCTM Standards: In kindergarten through grade 2 all students should relate ideas in geometry to ideas in number and measurement; recognize the attribute of area; compare and order objects according to this attribute; understand how to measure using nonstandard and standard units.
Teacher Notes: You can explore area without the requirement of a formula by using hands-on activities to help students understand the concept. In this lesson students will understand area as the number of square units inside a flat, two-dimensional figure, using paper tiles to represent one square unit. They will then compare the areas of different shapes to determine which is larger.
Lesson Plan
New words: area; area in square units
You will need: A copy of Pezzettino; enlarged color copies of animals from the book; various colored 1 square unit tiles cut from construction paper (1 cm or 1 inch depending on size of your copies of the animals); construction paper and glue sticks to construct an animal; overhead projector for modeling; pencils and paper for each group to record their findings.
Plan
Anticipatory Set and Objective: Tell children you are going to read a story about animals of different shapes and sizes. Discuss the size of shapes with students – which animals appear larger?
Input: Read Pezzettino to students stopping to look at the illustrations. Ask which animal is the largest animal. How can they decide which is the largest?
Modeling: Use a copy of the One-on-the-mountain and the unit tiles to begin to measure the area of the shape.
Guided practice: Group students into pairs. Hand out a copy of the One-on-the-mountain from the story and colored paper tiles. Using the tiles, have students fill in the entire area of the animal and determine the number of square units used. Call this the area. Students should record the area on paper.
Check for Understanding: Hand out copies of various other shapes from the book. Which do they think is the largest? The smallest? Again, using the tiles, have students fill in the entire area of their animal and determine the number of square units used. Record the area.
Which animal covers the largest area? Which covers the smallest area?
Independent Practice: Have each pair make an animal shape of their own and glue the shape on construction paper. You can display the animals in the classroom.
Students can apply the idea of area to many different shapes in their homes by determining the area of a table or any small shape using paper unit tiles. They can find a polygon shape in the home, trace or plot the shape onto paper and determine the area using the square unit tiles.