I found this idea while searching pinterest - a dangerous pastime, I know (name that movie!) - and I was so excited by the idea. I decided to expand the idea so that it could be used as a multiple day center. I also added an element of writing to the activity.
You use toothpicks to create different shapes. I used the flat ones that come in a box so that they didn't roll around.
The first day we made the shapes using the document I will link to below. (The shapes are custom made so the sides match the length of the toothpicks exactly.) We talked about each shape and how many sides it has. Then she used the toothpicks to create the shape.
Next, she traced the name of the shape, counted how many toothpicks she used, and wrote that number on her paper. - Because of the writing element of this part, this could take two days instead of one.
The next day, she used her paper and black construction paper to make the shapes without putting the toothpicks on top of the lines.
She checked how many toothpicks she would need for the shape, then used the picture of the shape as a guide to help her see what angles to use and what the shape looked like.
The last day, I gave her black construction paper, toothpicks and glue, and she made anything she wanted.
Here is the link for the document with the shapes and the tracing page. I wanted the sides to be exactly the length of one or two toothpicks so the shapes are custom made. You have to sign in to download the document, but it is really quick, easy, and unobtrusive.