Shape Up. SETTING THE STAGE Children sort figures according to basic attributes.

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1 Shape Up MA.C ,.2,.3, and.4; MA.C and.3 LESSON FOCUS Building models/diagrams to represent quantities between zero and one. COMPANION ANCHORS LESSONS Recognizing Shapes; Building Shapes; Polygons MATERIALS Excursions student pages, Teacher-made transparency of Excursions student page 125 (Shape cards) Shape Up TR1 Home Connection page 132 Sentence strip paper Scissors Envelopes for each student to keep shape cards (Cards will be used for other lessons.) Ball of yarn or string angle circle closed figure hexagon line line segment octagon LANGUAGE DEVELOPMENT pentagon polygon quadrilateral side triangle vertex vertices SETTING THE STAGE Children sort figures according to basic attributes. Display the transparency Shape Up TR1 on the overhead. Have children open their Excursions books to Shape Cards, page 125. Instruct children to cut out the squares so that they have 24 cards. When children have cut out all the cards, have them place the cards faceup on their desks. Explain to children that you would like them to separate the shapes into two different groups. Children may use any criteria they wish to separate them (number of sides, curved shapes vs. straightedged shapes, etc.) Once children have separated the shapes into two groups, have them share how they decided to separate or categorize the shapes. Explain to children that mathematicians have described certain attributes that allow us to separate shapes into different groups, or categories. Today, they will be looking at some different characteristics or attributes that these shapes have, and how they can use them to group the figures. LESSON OVERVIEW In this lesson, children sort shapes first by attributes that they define themselves and then by those presented by the teacher. In doing so, they develop an understanding of the components (line segments, vertices) of polygons and learn to differentiate them based on the number of sides and vertices they possess. Throughout the lesson, children are prompted to use the specific vocabulary of geometry to express their ideas. Note: As you discuss each vocabulary word with the class, draw an example on the board or post an example on a bulletin board to provide visual reinforcement. This way, whenever children need to respond verbally or in written form, they will be able to refer to the model to ensure that they are using the correct word. If you use a word wall, add appropriate words and terms as you work through the lesson. BUILDING CONCEPTUAL KNOWLEDGE Introduce specific terminology for plane figures. Write the following vocabulary words and terms on pieces of sentence strip paper: Line, Line Segment, Angle, Vertex, Closed Figure, Polygon, Side, Triangle, Circle, Quadrilateral, Pentagon, Hexagon, and Octagon. Write closed figure on the board. Explain to children that a closed figure is a shape that can be traced with the same starting and stopping points, without crossing or retracing any part of the figure. Draw an example of a closed figure on the overhead. Next to it draw an example of a figure that is not closed. 86

2 _HILL2.ExMap.TE 6/30/03 2:34 PM Page 87 Instruct children to separate the shapes on their desks into two categories: those that are closed figures and those that are not. When children complete this task, they should have figures 14 and 22 in one group and the rest of the shapes in the other group. Using the transparency, point out shapes 14 and 22 and explain why these shapes would not fit the attributes of a closed figure. Unravel a few feet of yarn from a ball. Hold up a segment of the yarn taut between your hands so that it forms a straight line. Tell children to imagine the whole ball unrolling and stretching in a straight line in both directions forever. Tell them that a line has no end, it is an idea that goes on forever. Then draw their attention to the section of yarn between your hands and say, A line segment is a part of a line with an end and a beginning. Write the term line segment on the board. Make sure children understand that line segments are straight and that they cannot be curved. Focus on attributes of polygons. Write polygon on the board or word wall. Tell children that a polygon is a simple closed figure formed from line segments. Draw a square, a circle, and an open figure comprised of three straight line segments on the overhead. Explain that only the square is a polygon. The circle is not made of line segments and the open figure is open. At this point you may want to single out shape 11 (circle). Describe a circle as a closed figure whose curved edge is always the same distance from a fixed point (the center). Children do not need to know the definition of a circle, but they should be able to tell the difference between a circle and shape 15 (an elipse). Instruct children to separate their shapes into two different groups: shapes that are polygons and shapes that are not. When children complete this task, they should have shapes 11,14,15,19, 21, and 22 in one pile (nonpolygons) and the rest of the shapes in the other group (polygons). Using the transparency, explain why the first group does not fit the attributes of a polygon and why the other group does. Instruct children to place all of the shapes that are not polygons off to the side. (Provide a baggie or envelope for each child s shapes, since these SHAPE CARDS NAME AND ATTRIBUTE CARDS Quadrilateral Polygon one hundred twenty-five 125 Exactly Eight Hexagon Exactly Five Angles Exactly Six Corners Simple Closed Figure Exactly Three Angles Circle No Pentagon Octagon Simple Closed Figure Not a Polygon Three Line Segments, Not a Polygon Hexagon Exactly Three Triangle Quadrilateral Exactly Five Exactly Ten one hundred twenty-seven 127 Page 125 Page

3 _HILL2.ExMap.TE 6/30/03 2:34 PM Page 88 shapes will be used again in a later lesson.) Explain to children that they are now going to be working only with polygons. Point to shapes 7, 8, and 12 on the overhead. Ask children if they know the name for this shape. Ask them to say how the three shapes are the same and how they are different. Write triangle on the board. Explain to children that a triangle is a polygon with exactly three sides and three angles. Children may know what a side is (a line segment connected to other segments to form a polygon), but they may not know what an angle is. Write angle on the board or word wall. Explain to children that an angle is formed when two line segments (or rays or lines) intersect. Have them look at the word triangle again. Underline angle and point out that the prefix tri- means three. Ask if they can think of another word with that prefix. (tricycle) Write vertex on the board. Explain to children that the name of the point where two line segments (or lines or rays) meet is called a vertex. The plural of vertex is vertices. Again, children do not need to know these definitions, but they do need to be able to recognize where angles are located and to count the number of vertices a shape may have. Using the overhead, display some shapes and point out where the sides, angles, and vertices are located. You may also want to point out some angles formed by intersecting line segments around the room. Sort polygons in terms of attributes. Instruct children to take their group of shapes (only polygons now) and separate them into two groups: triangles and nontriangles. When this task is completed, children should have figures 7, 8, and 12 in one pile (triangles) and all the other polygons in the other pile. Using the transparency, point out shapes 7, 8, and 12, and discuss what attributes make these shapes triangles while the other polygons are not. Continue in this same fashion, using the same grouping activity and similar questioning strategies for the remaining vocabulary terms: quadrilateral, a SHAPE CITY DIRECTIONS 5 Use the map on page 41 to answer the questions below. 1. What shape is the roof on the theater? rectangle MAP OF SHAPE CITY Theater Bank Art Museum one hundred twenty-nine Samantha s house has two hexagonal windows. Circle Samantha s house on the map. 3. Carlos s house has a large circular window and a quadrilateral-shaped roof. Put an X through Carlos s house. 4. Parker is looking for the art museum. How could you describe the museum so that Parker could find it? The museum is shaped like an octagon and has four pentagon-shaped windows. The roof is shaped like a triangle. (Answers will vary.) 5. The library has four quadrilateral-shaped windows. Put a box around the library. 6. How many quadrilaterals make up the shape of the bank building? three 7. How many different kinds of shapes were used to make the art museum? four one hundred thirty-one 131 Page 129 Page

4 four-sided polygon; pentagon, a five-sided polygon; hexagon, a six-sided polygon; and octagon, an eightsided polygon. BUILDING SKILLS AND STRATEGIES Children match shapes to names and attribute descriptions. Activity 1 Copy Excursions Shape Cards, page 125. If possible, laminate the page as these cards will be passed back and forth. Make enough copies so that you can give each child a shape card. Cut the cards out and give each child a shape card. Prepare attribute signs (exactly four sides) and name signs (hexagon) by cutting them out from and Attribute Cards, page 127. including, but not limited to the attributes and names included in the cards. Have each student stand with a shape card in his or her hand. Children will be doing a cooperative activity called Mix, Stop, Match, and Discuss. When you instruct children to mix, they will walk about the room and trade shape cards with whomever they encounter. While children are mixing, place one of the attribute or name signs that you have made in each corner of the room. When you say stop, children are to stop right where they are. If they were in the middle of trading, they can complete their trade, but they must keep the card they have. Children should inspect the shape card in their possession and look at the attribute or name signs that you placed in the corners of the room. While still stopped, children should make a decision on which attribute or name sign best matches the shape card in their hands. When you say match, children should walk to the corner of the room containing the attribute or name sign that matches their shape. If they cannot make a match, they should go to the center of the room. An example of a nonmatch might be a student with a pentagon shape in his or her hands, while the four corners are labeled triangle, 4 vertices, hexagon, and 8 sides. Since a pentagon does not match any of the corners, the student would go to the center of the room. Once children have walked to a corner or to the center of the room, say, Discuss. During this time, children will show the other children at their corner their shape cards and discuss why they chose the corner that they did. After children have had about a minute to discuss, you can call a few children up to the overhead. They can point out their shapes on the transparency of Shape Up TR1 and explain why they chose the corner that they did, or why they were a non-match. Start again by saying mix. There may be times that a student could choose more than one location in the room. For example, if you place a name sign that says polygon in one corner, many children could choose to go there even though their shape might also match another corner. Encourage them to comment on this. Activity 2 Practice matching shapes, names, and attributes. Have children open their Excursions books to the and Attribute Cards, page 127. Have children cut out the cards. If possible, laminate the pages beforehand as these cards will be used for a number of games. Each pair of children will also need one set of shape cards they used in the Building Conceptual Knowledge section and saved in an envelope for this activity. Instruct children to place their shape cards faceup on their desks. Have children shuffle the name and attribute cards and place them in a pile facedown on their desks. Partners will take turns turning over a name or attribute card. If there is a shape card left that matches the name or attribute, that player gets to claim that shape card and place it in his or her pile. Children may only take one shape card per turn, even though they may find more than one match. If a child cannot find a shape card that matches the attribute or name, he or she must place the card in the discard pile. Play continues back and forth between players until all of the attribute/name cards have been used and placed in the discard pile. The player who has claimed the most shape cards at the end wins the game. 89

5 _HILL2.ExMap.TE 6/30/03 2:34 PM Page 90 PUTTING IT INTO ACTION Children work cooperatively using lesson vocabulary to give directions. Place children in pairs. Have one child open his or her Excursions book to Map of Shape City, page 129, and the partner open to Directions to Shape City, page 131. Instruct children to read the directions carefully and complete the pages. HOME CONNECTION Have children turn in their Excursions books to Home Connection: that Shape, page 132. Read the directions with the children and tell them to take the page home and complete it with the help of a family member. Ask them to bring the page back to school and share their results with classmates. 90