I've done this with blues, greens and purples! I also added in white and glitter crayons. The white really makes the colors pop. It is hanging in my dining room. You would not believe how great it looks! Everyone who sees it is mesmerized, especially my 3 1/2 year old niece :) Fun Art! Whimsical and eye-catching!
Glue crayons on a piece of white cardboard then take a blow dryer and melt the crayons. then draw a silhouette of what you want. I did this with my daughter a year ago...worked really well. I glued the crayons on first with craft glue....also have a drop sheet out as it can get abit messy!!!