This grade 1 shapes worksheet answer key solves all 23 problems of the 2d and 3d shapes worksheet step by step.
This answer key explains each of the 23 shape problems. Check the number of sides and corners first. Then check whether a fact is defining. Pictures show how shapes fit together.
Grade 1 Shapes Worksheet Answer Key: problems 1–5
Problem 1: Naming shapes
A triangle has 3 sides and 3 corners. Shape B has 3 sides.
B is the triangle.
Problem 2: Counting sides
Touch and count each side: 1, 2, 3, 4.
The shape has 4 sides.
Problem 3: Counting corners
Count each corner: 1, 2, 3.
The triangle has 3 corners.
Problem 4: Square or rectangle
A shape with 4 equal sides and 4 square corners is a square.
It is a square.
Problem 5: Round shapes
(a) A circle is round. It has no straight sides. No.
(b) A circle has no corners. No.
(a) No. (b) No.
Grade 1 Shapes Worksheet Answer Key: problems 6–10
Problem 6: Color does not matter
Each shape has 3 straight sides and 3 corners. Color is not a defining attribute.
Yes, both are triangles.
Problem 7: Size and turn
Each shape is closed and has 3 straight sides and 3 corners. A shape stays the same when it is turned.
Yes, all three are triangles.
Problem 8: Defining or not
(a) Three sides are needed for a triangle: D.
(b) Color does not matter: N.
(c) Turning does not change a triangle: N.
(d) A triangle must be closed: D.
(a) D. (b) N. (c) N. (d) D.
Problem 9: Not a triangle
A is a triangle. D is a triangle that is turned. B has a gap, so it is open. C has 4 sides.
B and C are not triangles.
Problem 10: Drawing a shape
Draw 4 straight sides that are all the same length. Make 4 square corners.
The shape is a square.
Grade 1 Shapes Worksheet Answer Key: problems 11–15
Problem 11: Name the solid
A cone has one flat circle and a pointed top. Solid C has a pointed top.
C is the cone.
Problem 12: Solids in real life
(a) A can of soup has two flat circles: cylinder.
(b) A party hat has a pointed top: cone.
(c) A number cube has square flat sides: cube.
(a) cylinder. (b) cone. (c) cube.
Problem 13: No circles
A cone has 1 flat circle. A cylinder has 2 flat circles. A cube has only squares.
The cube has no flat circle.
Problem 14: Two triangles
Slide the triangles together. The longest sides touch.
They make a square.
Problem 15: Two squares
Slide the squares together.
The new shape has 4 sides and 4 square corners, but two sides are longer.
They make a rectangle.
Grade 1 Shapes Worksheet Answer Key: problems 16–20
Problem 16: Two half circles
Put the straight edges together.
They make a circle.
Problem 17: Counting cubes
Count from the bottom: 1, 2, 3, 4, 5.
There are 5 cubes.
Problem 18: Sofia builds a house
A square has 4 sides. A triangle has 3 sides.
\(4 + 3 = 7\)
The two shapes have 7 sides in all.
Problem 19: Jamal joins squares
Count by twos: 2, 4, 6. That is 3 pairs.
Jamal can make 3 rectangles.
Problem 20: Two towers
\(4 + 3 = 7\)
They use 7 cubes in all.
Grade 1 Shapes Worksheet Answer Key: problems 21–23
Problem 21: Aisha cuts squares
Each square makes 2 triangles. \(2 + 2 = 4\), then \(4 + 2 = 6\).
Aisha will have 6 triangles.
Problem 22: Mystery shape
(a) 4 equal sides and 4 square corners is a square.
(b) One square has 4 corners. \(4 + 4 = 8\).
(a) A square. (b) 8 corners.
Problem 23: Sorting solids
(a) \(3 + 4 = 7\), then \(7 + 2 = 9\).
(b) Cylinders: 4. Cubes: 2. \(4 – 2 = 2\).
(a) 9 solids. (b) 2 more cylinders.
How to use this grade 1 shapes worksheet answer key
Read this grade 1 shapes worksheet answer key after trying each problem yourself, and redo any problem you missed.
See every chapter on the Grade 1 math page.
