Plane Shapes

The CCSS have supplied a more in-depth goal for my first graders to master than the previous state supplied standard of just being able to identify plane shapes. CCSS expects first graders to be able to distinguish between defining and non-defining attributes of shapes and categorize them accordingly (1.G.A.1). Defining attributes have to do with the number of sides and corners, like a triangle has 3 sides and 3 corners, yet a circle has none.  Non-defining would be one is larger than another or the colors are the same. I want them to see that even if they are different colors or sizes, they are still that category of shape. The defining attributes of that shape create a structure we can use to categorize shapes (MP7). Certain attributes are critical while others are not; the structure of the shape matters. 

I will get my students thinking about shapes by playing with Geo boards. My students have not played with Geo boards this year and I will definitely have to give them play time with them before they can use them as math tools.

I will allow 5 minutes of free play with Geo boards and then advance to our lesson. 

First, draw the following shapes on the board: circle, square, rectangle, and triangle.

Students, we have worked with these shapes before and I need your help labeling them. Which one is the triangle? How do you know? Which is the square? How do you know? (I will continue to write the names next to the shapes until all are labeled.)

Now we will have a discussion about these shapes as a review. My class has already been taught shapes have defining attributes which are determined by the amount of sides, vertices, curves, and whether they are open and or closed. Our discussion to identify attributes will involve comparing shapes with one another and determining similarities or differences based on essential attributes.

Some questions I will cover are:

• What is the difference between a triangle and square? (triangle has 3 sides/vertices and a square has 4)
• What makes a square an example of a special rectangle? (it has 4 equal sides and vertices)
• What is special about a circle? (it has 0 vertices)

Second, I will open up this Smartboard image and have my class assist me in completing the chart about our shapes that we have discussed.

Third, I will encourage them to build each image on their Geo boards. I am not going to point out to the class that it is impossible to build a circle or oval on the Geo board. I am going to wait for someone to point it out to me and use it as a discussion point about sides and curves.

I want to be able to check for their understanding of shapes and see if everyone has mastered the identification of each one we have discussed. I will pass out one piece of large construction paper to each student and give the following verbal instructions, one problem at a time. I will allow them to draw their answer before I advance to the next problem.

• In box #1, draw 3 circles and 1 triangle. 
• In box #2, draw 1 rectangle and 2 circles.
• In box #3, draw 2 squares and 2 circles and 2 triangles. 
• In box #4, draw a playground using all the shapes. 

As they drew their pictures we continued to discuss shape attributes because I wanted to remind them they must be careful as they are drawing their shapes to give it the correct lines or curves or amount of corners (1.G.A.1)(MP7).

To finish up our lesson I am going to allow them 5 minutes of time with the Geoboards to construct a picture using the plane shapes we just discussed.

There will be two rules to follow: Students, you must construct a picture using plane shapes and your plane shapes must be constructed with the correct attributes.

I love the multiple shapes this student used to build a house.