3D and 2D Geometric Connections: Using a real-life object to make that demonstration

I took a regular Kleenex box and showed my 1st grade students step by step what 2D shapes makes a rectangular prism.  They made connections between the 3D rectangular prism and 2D rectangular and square shapes using a Kleenex box.  I cut the Kleenex box and pasted each face to chart paper.  We discussed the edges, faces and vertices of the rectangular prism.  Before this lesson, we made a compare and contrast Venn diagram between a rectangular prism and cube.   It's important for my students to have that solid foundation and understanding of the different geometric shapes.