I was thinking about the different ways I could put you all into groups, and I thought about how you are all KIPPsters, you are all 3rd graders, you are all part of the Crimson Tide classroom. All of these different names are ways that our class can be described. Well, shapes can do that, too! 2D shapes can also be called Polygons. And 2D shapes with 4 sides can all be called quadrilaterals. Look at this shape. Turn to your partner and talk to them what names you can use to describe it. (MP7)
Students should respond square, polygon and quadrilateral. I record this on the board. Although students do a lot of work with geometry in previous grades, I find that students often forget the accurate names of shapes, attributes and ways to organize similar shapes.
Everyone take a look at your 2D shape reference sheet. Take a minute to turn and talk to your partner about what you notice about the shapes and record anything you see that the shapes might have in common. Write down all of your thoughts so that we can discuss and learn from each other!
Discussion and turn and talk can be used in order to include all students in the discussion and inquiry. Today my focus is to ensure that students are talking about and thinking about things that are similar about the shapes.
You and your partner will have a chance today to look around our room for real world example, or think of examples that you’re familiar with, to create a list of real world items that fit into our shape categories (mp2). Make sure that you work together and help one another, because the more we all learn, the better we all become!
There are 2 purposes for making this activity a partner activity. First, students who work together naturally discuss, debate and provide reasons to their partner (MP3) for why a particular shape does or does not fit into a category. Secondly, I want students to make that real world geometry connection to things within our classroom.
With my students, the real world connection is critical. Students need a 'reason' to think about and remember math, and when it connects to their world it makes more sense to them.
Who would like to share some of the real world objects they discovered today? And what about things that were similar.
We end the day with a conversation around what they discovered. This is a time I can catch and correct any misconceptions immediately and use that information for tomorrow’s lesson.
One of the misconceptions - giving the names of 2D shapes to 3D shapes - is perpetuated by media where rather than use a more complex vocabulary (e.g. rectangular prism), a 3D shape will be called by its 2D name (rectangle). Misconceptions also arise from a lack of awareness or poor/confused understanding of the attributes of a shape. Vocabulary could be part of this problem. If shapes are described using the proper math vocabulary, and a student doesn't know what those words mean, they won't be able to understand what is being discussed. This is one reason it is important for students to have frequent, rich, opportunities to explore and discuss shapes as this provides the context for learning the attributes and the vocabulary which describes them.