This is one of my favorite lessons to teach because it is all around us and they know exactly what they are and don't know it.
Let's start with a One Dimensional Lines. Simple, it's the distance between two points. Every time we measure the distance between to things we are using one dimension.
Here's where it gets fun, Two Dimensional Objects!
Ask them how many of them used to have a regular Nintendo System or have seen one before. How many of them have played the original Mario Brothers game? In the game you can tell how tall Mario is and how thick (or fat depending on how well you know your kids  they will laugh) Mario is. However, you can't see how Wide Mario is. He runs and jumps but he never turns to the side so we can see his width. That's because the original Nintendo System and most old game systems were made in Two Dimensions.
Move a few years in the future. The Nintendo 64 comes out or really any Nintendo after that. On these systems we can now see Mario move in all directions. We can see he is wide, he is short, and he has a big belly. That's because Mario is now in 3D or Three Dimensions. He had a height, a width, and a thickness (or length).
You don't have to use this example there are many things you could relate this to. I can guarantee you though if you start talking about video games in class or cell phones or something they use regularly they will be locked in and paying attention! If you want our lesson plans, worksheets, and assessments that go along with this lesson and all of our others simply click the link below to join!
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