Shapes and Their Attributes

Transcription

1 Name Shapes and Their Attributes Topic 15 Standards 2.OA.C.4, 2.G.A.1, 2.G.A.2, 2.G.A.3 See the front of the Student s Edition for complete standards. Home-School Connection Topic 15 Dear Family, Your child is learning to identify and draw two-dimensional shapes and three-dimensional cubes. He or she will use vocabulary associated with these shapes. Your child will also partition a rectangle into rows and columns of equal-sized squares and count to find the total number of squares, as shown below. This is an important foundation skill and used when finding the area of rectangles. You can count and add the number of squares that cover this rectangle in different ways. Add by rows: = squares Add by columns: = squares Counting Squares Materials Grid paper, scissors Have your child cut out a small rectangle like the one above from a piece of grid paper. Then ask your child to count the number of squares by rows and by columns. Help your child see that the total number of squares is the same using either way. Repeat the process several times after having your child cut out rectangles of different shapes and sizes. Challenge him or her to write addition equations that show the number of squares by rows and by columns. Observe Your Child Focus on Mathematical Practice 8 Look for and express regularity in repeated reasoning. Help your child become proficient with Mathematical Practice 8. Ask your child to explain how counting squares by rows or by columns repeatedly is a shortcut for counting them individually.

2 Nombre Las figuras y sus atributos De la escuela al hogar (en español) Tema 15 Estándares del Tema 15 2.OA.C.4, 2.G.A.1, 2.G.A.2, 2.G.A.3 Los estándares completos se encuentran en las páginas preliminares del Libro del estudiante. Estimada familia: Su niño(a) está aprendiendo a identificar y dibujar figuras bidimensionales y cubos tridimensionales. Usará el vocabulario asociado con estas figuras. También dividirá un rectángulo en filas y columnas de cuadrados del mismo tamaño y contará para hallar el número total de cuadrados, como se muestra a continuación. Esta es una base importante que se usa cuando se halla el área de los rectángulos. Se puede contar y sumar el número de cuadrados que cubren este rectángulo de diferentes maneras. Sumar por filas: = cuadrados Sumar por columnas: = cuadrados Contar cuadrados Materiales Papel cuadriculado, tijeras Pídale a su niño(a) que recorte un rectángulo pequeño, como el que se muestra arriba, de un pedazo de papel cuadriculado. Luego, pídale que cuente el número de cuadrados por filas y por columnas. Ayude a su niño(a) a ver que el número total de cuadrados es el mismo con cualquier método. Repita el proceso varias veces después de pedirle a su niño(a) que recorte rectángulos de diferentes formas y tamaños. Anímelo(a) a escribir ecuaciones de suma que muestren el número de cuadrados por filas y por columnas. Observe a su niño(a) Enfoque en la Práctica matemática 8 Buscar y expresar uniformidad en los razonamientos repetidos. Ayude a su niño(a) a adquirir competencia en la Práctica matemática 8. Pídale que le explique por qué contar los cuadrados por filas o por columnas es más rápido que contarlos individualmente.

3 Building Blocks Written by Bill Whitney Illustrated by Mike Dammer This book belongs to: TOPIC 15 Story Lisa makes a bigger tower. She uses cubes. Count the vertices on a cube. How many vertices are there? fold down Lisa makes a town. She uses cylinders. Count the flat surfaces on a cylinder. How many flat surfaces are there? Topic 15 4 Topic 15 1

4 Jim makes a bigger town. He uses cylinders. Count the edges on a cylinder. How many edges are there? fold down Jim makes a tower. He uses cubes. Count the flat surfaces on a cube. How many flat surfaces are there? Topic 15 2 Topic 15 3

5 Name Reteach to Build Understanding 15-1 Vocabulary 1. The vertices of a two-dimensional shape are its corners. You can name a shape based on the number of sides and vertices it has. These shapes are all pentagons. A pentagon has A pentagon has sides. vertices. 2. Triangles have sides and vertices. Cross out the shape that doesn t belong. 3. Quadrilaterals have sides and vertices. Cross out the shape that doesn t belong. A square is a quadrilateral with 4 equal sides. Draw a square. On the Back! 4. A hexagon has 6 sides and 6 vertices. Draw a hexagon. Circle the vertices. R 15 1

6 Play a Game Partner Talk Share your thinking while you work. Start Get 12 red squares. Cover each game space with a square. Take turns. Try Uncover two game spaces. If the two shapes have the same number of vertices, explain why. Keep the squares. If not, put the squares back where they were. Take turns until all the spaces are uncovered. To win, collect the most squares. Try Again Play again! Center Game 15 1

7 Play a Game Partner Talk Share your thinking while you work. Start Get 12 red squares. Cover each game space with a square. Take turns. Try Uncover two game spaces. Do you see one shape and a way to describe that shape? If you do, name the shape and read the words. Keep the squares. If not, put the squares back where they were. Take turns until all the spaces are uncovered. Four angles Five vertices Six vertices Six sides Five angles Four sides To win, collect the most squares. Try Again Play again! Center Game 15 1

8 Name Reteach to Build Understanding 15-2 Vocabulary 1. A polygon is a closed plane shape with 3 or more sides. The sides of a polygon are straight. Two sides of a polygon form an angle. A right angle forms a square corner. This polygon has angles. of the angles is right. side angle right angle The name for this polygon is. 2. Write the number of angles and then name the shape. Shape: 5 angles pentagon Shape: angles angles angles Shape: Shape: On the Back! 3. Draw a polygon with 6 sides. Make two of its angles right angles. Then name the shape. R 15 2

9 Name Vocabulary 1. A polygon has an equal number of sides and vertices. These polygons each have Reteach to Build Understanding 15-3 sides and vertices. They are called. Trace each shape. 2. The same kind of polygon can look different. Here are three quadrilaterals. Trace each shape. Sides can have the same length, or they can be different. All three quadrilaterals have sides and vertices. 3. Draw a quadrilateral that looks different from the two above. It must have sides and vertices. On the Back! 4. Draw a polygon with 1 more side than a quadrilateral. How many sides must it have? Write its name. R 15 3

10 Name Building with Shapes Math and Science Activity 15-3 Did You Know? Houses are made up of different shapes. A triangle can be used to make a slanted roof. Water flows better off a slanted roof. 1 Follow these instructions to draw a house. Draw the front of the house. It will be a polygon with 5 vertices. Draw a 4-sided door with opposite sides the same length. Draw 2 windows, one on both the left and the right sides of the door. Each window is a polygon with 4 sides that are the same length. Draw another window with 3 vertices over the door. 2 Name the polygon you drew for each part of the house. Front: Windows on the left and right sides of the door: Door: Window above the door: 3 Extension Use shapes to draw another house on the back of this paper. Trade drawings with a partner. Describe and name the shapes in your partner s drawing. Math and Science Activity 15 3

11 Name Vocabulary 1. A cube is a solid figure with 6 equal square faces, 12 edges, and 8 vertices. Reteach to Build Understanding 15-4 These are cubes. These are NOT cubes. face edge vertex Draw an arrow from each shape to its correct box. 2. Tell whether each shape is a cube. Then explain why or why not. Yes No Yes No Explain: Explain: On the Back! 3. Find an object at home or at school that is a cube. Describe the object. Tell how many faces, edges, and vertices the object has. R 15 4

12 Name Cubes Around Us Math and Science Activity 15-4 Did You Know? Blocks, ice, and boxes can be in the shape of a cube. The shape of a cubic block lets you stack and build with it. Each time you toss a number cube, one of the 6 numbers will be on the top face. 1 Naomi has a number cube. Complete each description of a number cube. The number cube is a figure. It has faces. It has edges. It has vertices. Each face of the number cube is a. 2 Describe two more features that you know about a cube. 3 Use the dot paper to draw a cube. Use dashed lines to show the edges that you can t see. 4 Extension Find an object in the shape of a cube at home or at school. Draw the object. Explain why a cube is a good shape for the object. Math and Science Activity 15 4

13 Name Vocabulary 1. This rectangle is covered with squares. You can use square tiles to cover a rectangle with squares. Count the squares. Add the squares by rows, or add the squares by columns. row column Reteach to Build Understanding 15-5 Add by rows: = Add by columns: = 2. Use square tiles to cover the rectangle. Trace the tiles. Count the squares By rows: + + = By columns: = On the Back! 3. Draw a rectangle that is divided into equal squares. Show counting the squares by rows and by columns. R 15 5

14 Look and See Partner Talk Share your thinking while you work. Start Get Get 10 red squares. Work together. Try Point to a rectangle. Use red squares to cover the rectangle. Count the number of equal squares. Use a number tile to show the number of squares. Squares Squares Squares Squares Squares Try Again Can you add rows of squares to find the total in each rectangle? Write an equation to find each sum. Center Game 15 5

15 Look and See Partner Talk Share your thinking while you work. Start Get Get 10 red squares. Work together. Try Choose a rectangle. Estimate the number of red squares needed to cover the rectangle. Use squares to find this number. Count the squares in rows. Use a number tile to show this number. Squares Squares Squares Squares Squares Try Again Talk about objects in your classroom that you can measure with the red squares. Estimate the number of squares needed to cover them. Center Game 15 5

16 Name Vocabulary 1. Equal shares have the same size and shape. Reteach to Build Understanding 15-6 Both shapes have shares. Circle the shape that has equal shares. 2. Count the equal shares. This triangle has equal shares. 2 The shares are called. Each equal share is a 3. Count the equal shares. the whole. Names for equal shares: halves thirds fourths This triangle has equal shares. The shares are called. Each equal share is a the whole. On the Back! 4. Show 2 equal shares of a circle. Show 3 equal shares of a square. Show 4 equal shares of a rectangle. Write the names for the equal shares. R 15 6

17 Try Together Partner Talk Share your thinking while you work. Start Put in a. Take turns. Try Pick a tile. Place it under a shape with that number of equal shares. equal shares equal shares equal shares equal shares equal shares equal shares equal shares equal shares Try Again Put the tiles back in the. Try again. If a shape is split into equal shares, tell if the shares are halves, thirds, or fourths. Center Game 15 6

18 Try Together Partner Talk Share your thinking while you work. Start Put in a. Take turns. Try Pick a tile. Place it under a shape with that number of equal shares. equal shares equal shares equal shares equal shares equal shares equal shares equal shares equal shares Try Again Put the tiles back in the. Try again. Talk about what you have tried to split into equal shares and why. Center Game 15 6

19 Name Vocabulary 1. You can divide a rectangle into equal shares. Both rectangles show 2 equal shares. Reteach to Build Understanding 15-7 The equal shares can be different shapes. For shares to be equal, they must be the same size. How many squares are in each equal share? 2. Draw lines to show two different ways to divide the same shape into 2 equal shares. How many squares are in each equal share? How many squares are in each equal share? On the Back! 3. Draw a large rectangle. Cover the rectangle with 12 smaller squares. Draw lines to show a way to divide the rectangle into 3 equal shares. Tell how many squares are in each equal share. R 15 7

20 Play a Game Partner Talk Share your thinking while you work. Start Get 12 red squares. Cover each game space with a square. Take turns. Try Uncover two game spaces. Do you see one divided shape and the word Equal or Unequal? If you do, keep the squares if the word describes the shares. If the word does not describe the shares, tell why and put the squares back where they were. If you do not uncover one divided shape and one word, put the squares back where they were. Take turns until all the spaces are uncovered. Equal Unequal Unequal Equal Equal Unequal To win, collect the most squares. Try Again Play again! Center Game 15 7

21 Play a Game Partner Talk Share your thinking while you work. Start Get 12 red squares. Cover each game space with a square. Take turns. Try Uncover two game spaces. Do you see one divided shape and a way to describe that shape? If you do, tell how many squares are in each equal share. Keep the squares. If not, put the squares back where they were. Take turns until all the spaces are uncovered. 4 equal shares 2 equal shares 3 equal shares 4 equal shares 3 equal shares 2 equal shares To win, collect the most squares. Try Again Play again! Center Game 15 7

22 Name Vocabulary 1. You can draw lines to divide a shape into equal shares. Then you can make a design by coloring each of the shares a different color. Reteach to Build Understanding 15-8 Marco wants to color this rectangle with 3 colors. Each color must have an equal share. How many squares will be in each share? Use repeated reasoning. Show two ways Marco can color the rectangle. 2. Use the rectangles at the right to make two different designs. Each design must have 4 colors with an equal share for each color. Design 1 Design 2 How many squares will be in each share? 5 On the Back! 3. Draw a rectangle that is divided into 10 squares. Show two different ways to color the rectangle with 2 colors. Each color must have an equal share. R 15 8