Yes, I'm still experimenting with silhouettes! These were created by a year four class. I asked them to make a large outline of their chosen object in pencil and then had them rule their own background stripes using dimensions written on the board. Using regular acrylic paint, the students painted their silhouettes and the stripes in primary colours, leaving one white. Each student decided which colour should go where. The paints were wet on the paper so I was pretty impressed by how well they controlled their brushes.
We briefly discussed how some famous artists and artworks were renowned for utilising the three primary colours plus black and white. From memory I only talked about Mondrian although Lichtenstein is another good example. Please feel free to let me know of any other artists who have used this sort of primary colourway.