If I have time, I begin the activity with a "looking at art" session where students tell what they notice in Alexander Calder's lithograph, Stars and Stripes Students are generally quick to notice that Calder used only red and blue, and that it reminds them of the American flag, or the 4th of July. They often notice that the piece has more red than blue, and that one of the stars has a dot in the middle of it.
As part of the lesson, I teach 2nd grade and older students how to make a "quirky star" by drawing a circle in the center of a yellow square, drawing five dots around the circle, then connecting the dots to the circle, in sequence (it's easier than it sounds). First graders just draw and cut out a yellow star, and Kindergartners get a pre=printed yellow star which they are asked to tear out. I never give the students pre-cut stars because I want the stars to be quirky, asymmetrical, and fanciful.
This lesson is pretty much fool-proof; anything students come up with looks great!