You need fun foam scraps, foam core board scraps, paint and brushes, gluestick, and cardstock. If you want to skip the who stencil part, you could use striped and starry cardstock.
Trace at least 4 stars per each decoration you want to make. The stars need to have 1 line of symmetry. I used white and blue cardstock.
This will make 1 finished star.
Cut shapes from the fun foam to make stencils. Glue the shapes to foam core board with the gluestick. The shapes don't have to be perfect. (In the words of Severus Snape.... "Oooobivously.")
Now stamp away. I liked using various directions and color intensity. (That means you can stamp more than once without reloading if you want.) Don't try to stay in the lines. You will need 2 striped stars and 2 starry stars for each decoration.
Cut a line up the center of of the striped star. Stop about 1 inch from the top. (Where the scissors end in this picture.) You might want to draw a dot to show a child how far to cut.
Cut down 1 inch from the top center on the starry star.
Now slip the striped star onto the starry star and Voila! Stars and Stripes in 3-D!