CM: Compare the areas of regular and irregular shapes by informal means (ACMMG087 - Scootle )
CM: Compare objects using familiar metric units of area (ACMMG290 - Scootle )
Achievement Standard:
- Students compare areas of regular and irregular shapes using informal units.
- By the end of Year 4, students choose appropriate strategies for calculations involving multiplication and division.
CM: Compare objects using familiar metric units of area (ACMMG290 - Scootle )
Achievement Standard:
- Students compare areas of regular and irregular shapes using informal units.
- By the end of Year 4, students choose appropriate strategies for calculations involving multiplication and division.
Twelve Tiles
Twelve Tiles
Ask students to use 12 tiles to construct as many different rectangles as possible and record each one on grid paper. Have students order the shapes by the distance around each one. Ask: Can you order the shapes by their area? Why? Why not?
Ask students to use 12 tiles to construct as many different rectangles as possible and record each one on grid paper. Have students order the shapes by the distance around each one. Ask: Can you order the shapes by their area? Why? Why not?
a) 360 + 60 = b) 170 + 50 = c) 750 + 70 = d) 180 + 40 =
Comparing Polygons
Warm Up:
WALT: Compare and calculate the area of polygons (regular shapes)
WILF: We keep our equipment organised & follow instructions
WILF: We keep our equipment organised & follow instructions
Comparing Polygons
Organise students into pairs and give each pair a pattern block hexagon, square and triangle. Ask students to order them by area.
Organise students into pairs and give each pair a pattern block hexagon, square and triangle. Ask students to order them by area.
Big Foot
Warm Up:
a) 8 + 6 + 4 +2 = b) 1 + 7 + 9 + 3 = c) 5 + 2 + 8 + 5 = d) 9 + 3 + 0 + 1 + 7 =
WALT: Use a footprint to compare area using mathematical language
WILF: Humanity = we say please and thank you & we look for solutions
WILF: Humanity = we say please and thank you & we look for solutions
Bigger Foot
Tell students you heard someone say, ‘I’ve got a bigger foot than you.’ Ask: What measurements do you think they were thinking of? Organise students into pairs and invite them to make a cut-out shape of their foot. Encourage them to talk about the length, width, perimeter and area of their foot in comparison to their partner’s foot. For example, ask: Is your foot longer than Ahmed’s? Is it wider? Is it further around? Does it take up more space?
Tell students you heard someone say, ‘I’ve got a bigger foot than you.’ Ask: What measurements do you think they were thinking of? Organise students into pairs and invite them to make a cut-out shape of their foot. Encourage them to talk about the length, width, perimeter and area of their foot in comparison to their partner’s foot. For example, ask: Is your foot longer than Ahmed’s? Is it wider? Is it further around? Does it take up more space?
Leaves
Warm Up:
a) 60 + 70 =
b) 90 + 30 =
c) 800 + 400 =
d) 500 + 600 =
b) 90 + 30 =
c) 800 + 400 =
d) 500 + 600 =
WALT: Calculate the area of irregular shapes such as leaves with accuracy.
WILF: Belonging = participate & be prepared to negotiate
WILF: Belonging = participate & be prepared to negotiate
Leaves
Invite students to trace around a leaf and arrange whole 2-centimetre- squared tiles in ways that get the most into the area of the leaf. Ask: How could you fit another tile in? Will cutting it up help? Encourage students to keep track of how many tiles they have used with the fewest gaps, no overlaps and filled as close as possible to the edge of the outline of the leaf. Later, when students have become very careful about leaving no gaps or overlaps, draw attention to the way some have arranged tiles to make the job easier
Invite students to trace around a leaf and arrange whole 2-centimetre- squared tiles in ways that get the most into the area of the leaf. Ask: How could you fit another tile in? Will cutting it up help? Encourage students to keep track of how many tiles they have used with the fewest gaps, no overlaps and filled as close as possible to the edge of the outline of the leaf. Later, when students have become very careful about leaving no gaps or overlaps, draw attention to the way some have arranged tiles to make the job easier
Garden Plots
Warm Up:
Garden Plots
Have students explain why the same things may have been ordered in different ways. For example, say: Here is a problem some students were asked to work out. Their school had two pieces of land, one a rectangle and one a triangle. The school wanted to choose the largest one for a garden bed. Joshua thought the rectangular garden was bigger than the triangular bed, but Su-Lin thought the triangle shape was bigger. Ask: Why did the students think different things? What could Joshua be using to help him make his decision? How could you tell for sure which piece of land was bigger?
Have students explain why the same things may have been ordered in different ways. For example, say: Here is a problem some students were asked to work out. Their school had two pieces of land, one a rectangle and one a triangle. The school wanted to choose the largest one for a garden bed. Joshua thought the rectangular garden was bigger than the triangular bed, but Su-Lin thought the triangle shape was bigger. Ask: Why did the students think different things? What could Joshua be using to help him make his decision? How could you tell for sure which piece of land was bigger?
How long is a piece of string?
Perimeter and Area
Organise students into pairs and give each pair a geoboard and a piece of string. Have them tie a knot in the piece of string at 24 centimetres and use it to construct a shape with a perimeter of 24 centimetres. Invite students to make other shapes with the same perimeter. Have them record each shape on grid paper. Ask: How does the size of the area change?
Organise students into pairs and give each pair a geoboard and a piece of string. Have them tie a knot in the piece of string at 24 centimetres and use it to construct a shape with a perimeter of 24 centimetres. Invite students to make other shapes with the same perimeter. Have them record each shape on grid paper. Ask: How does the size of the area change?
Swimming Pool Dreams
Swimming Pools
Have students draw different shapes that have the same area. Say: A swimming pool company charges the same price to build any swimming pool, no matter what shape, so long as it has a water surface area of 18 square metres. Invite students to design different-shaped pools and demonstrate that the pools all have a surface area of 18 square metres.
Have students draw different shapes that have the same area. Say: A swimming pool company charges the same price to build any swimming pool, no matter what shape, so long as it has a water surface area of 18 square metres. Invite students to design different-shaped pools and demonstrate that the pools all have a surface area of 18 square metres.