Area and Perimeter Third Grade

Day 1

How Big is a Foot?

How big is a foot? Ask the students, “How big is a foot?” Have a general discussion or turn & talk. Have them trace their foot onto the back side of centimeter grid paper, and cut out. (Will use the cm side in a future lesson).

How Big is a Foot? http://www.youtube.com/watch?v=bWhWL1MET7A

What was the apprentice’s idea? Read the book to students using Elmo (for pictures) or show the story through YouTube. Stop after the apprentice is in jail…after it says “He thought…and suddenly had an idea.” Ask, “What do you think his idea was?” Students will discuss in groups.

Build the Bed Reflect on what the apprentice was thinking. Can we act this out? Build the bed using the apprentice’s foot. Each group share thoughts about the apprentice’s thinking Ask, “I wonder if we can act this out?” Select a small child’s foot (to act as the apprentice) ….can act like you’re drawing a name from a hat. Select a tall queen (can wear the crown) to lie in the bed. Go ahead and tape the bed (into rectangles) without using the vocabulary of area or perimeter.

Build the Bed...Again Cut out the King’s foot. Build the bed again using the King’s foot! Build it right next to the other bed. You will have the king’s foot cut out (exactly a foot long). Build the bed again with this measure (right next to the other bed).

Reflect Why is one bed larger than the other? Didn’t we use the same number of feet to make both beds? Turn & Talk, then write a reflection. Question students: Why is one bed larger than the other? Didn’t we use the same number of feet to make both beds? Have students turn and talk, then write a reflection. Finish book

Day 2

How big is the King’s foot? We will measure the King’s foot from the top of the big toe to the back of the heel. Have copies of the king’s foot for everyone. Guide them through using a ruler to measure the king’s foot (from top of big toe to back of heel).

Floor Tiles Look at our classroom floor. Each square on the floor is a tile. We are going to give you a paper floor tile that will serve as a model. Give each group a floor tile and rulers. Have them observe and record in math notebooks. Select points for discussion (for Congress) as you rotate around the room. All four sides are the same length It is a square It is 12 inches or 1 foot Conduct a Congress to bring out these points & record on flip chart. Conclude congress with the term square unit.

Tile Observation Observe everything you can about the your tile. Discuss your observations. Record your observations in your math notebook. Give each group a floor tile and rulers. Have them observe and record in math notebooks. Select points for discussion (for Congress) as you rotate around the room. All four sides are the same length It is a square It is 12 inches or 1 foot

Math Congress Floor Tile Observations Select points for discussion (for Congress) as you rotate around the room. All four sides are the same length It is a square It is 12 inches or 1 foot Conduct a Congress to bring out these points & record on flip chart. Conclude congress with the term square unit.

Day 3

How much space does the bed cover? Use your tiles go determine how much space the bed covers. Ask the students, “Can you figure out how much space the bed covers?” You want them to use the tiles they observed and build the taped off king’s bed. Have them determine this is how you could do it. They will all participate because it will take 18 of the tiles to cover the surface. Ask them how much space does the bed cover? They may say “18”; ask 18 what? Lead them back to the size of 1 tile (1 square foot)….to try to get them to say 18 square feet.

Two ways to record square feet There are two ways to record square feet. Write these in your math journals. 18 sq ft OR 18 ft Have them record the two ways to write square feet in their math journals. The only mathematical abbreviation measure that needs a period is in. because it can be confused with the word “in”. Go back and record on the classroom flip chart: 1 sq ft & 1 ft2 Introduce the word, “area” 2

What is Area? Area is the amount of space a shape takes up. Record the definition of area in your math journals.

Estimating Area You are going to estimate the area of several shapes round our school. Remember, an estimate tells us “about” how many. You will estimate the area of each shape in square feet, using your color tiles as a tool. Explain how the scavenger hunt will work. Hand out the recording sheets. Go over which items they will look for inside the school.

Scavenger Hunt – Inside Rectangular shape in hall Tile design in hall 3. Glass Window in hall 4. Bottom part of bathroom wall

Scavenger Hunt continued… 5. Exterior Door Window Pane 6. Water Fountain Rug 7. Black Millionaire poster 8. Front Side of Book Cabinet

Estimating Area – Recording Sheet Go over the recording sheets with students prior to beginning the Scavenger Hunt.

Day 4

Small Tile Observation Observe everything you can about the your tile. Discuss your observations. Record your observations in your math notebook. Give each group a floor tile and rulers. Have them observe and record in math notebooks. Select points for discussion as you rotate around the room. All four sides are the same length It is a square It is 1 inch Discuss observations as a class. Record square inch or in.2 on flip chart.

Color Tiles What is the area of one floor tile in square inches? Work in your group to determine how many square inches are in one floor tile. With a partner in your group, create a poster to explain how you found the area of the tile. Ask students, “What is the area of one floor tile in square inches?” Put students in groups based on the number of one inch tiles available (it takes 144 tiles for each tile) Students will work in groups to determine the area of one floor tile. Work with a partner to explain how you found the area of the tile. Teacher will rotate around the room to ask questions and look for efficient strategies. Congress- choose the most efficient strategies.

Day 5

Only complete the area column After test Only complete the area column After students finish the common assessment, they will practice finding the area of various objects in sq in., recording on a graphic organizer. Students need to complete the area column- explain to students that they will complete the perimeter column another day.

Day 6 - Finding Area in Square Inches Width Length 1 Use the various rectangles and squares from 2011 – 2012 plans, week 32-34 Area and Perimeter. There are 24 figures. Students will use one inch tiles to find the area of each numbered figure. TSW use the graphic organizer to record the length and width and area in square inches.

Day 7 – Area in Square Centimeters 8 5 Students will choose two numbers from a bucket to use as the dimensions for an array. (See Printable Numbers) TSW draw one rectangular array with the chosen numbers on centimeter grid paper. TSW will cut out the array and write their class number on the back. Lay out the arrays on each desktop. TSW rotate among each table to find the area for each array. TSW will number 1 – 20 to represent the class numbers in their math notebooks to record the L X W = A for each array.

Day 8 – How Long? How Many? 2x3=6 4x5=20 Use Marilyn Burns, About Teaching Mathematics, page 242, model How Long? How Many? With class. Directions for Game: Roll the die twice to find the dimensions for an array. On the 10 X 10 grid, shade the array, and label the equation. Explain that now the partner will roll and shade their array on their own grid. Continue play until one player fills in their 10 X 10 grid. Players will add up the products to make sure they add up to 100. The other player will add products to see how close they came to 100. TSW may repeat the game as many times as needed. Classwork (see classwork on website)

Day 9 – Test & Activity

Day 10 -