When the children color the quilts you can use regular coloring crayons and not have to buy the fabric ones. I did this type of project with school children. After coloring the fabric and ironing it (use old paper bags to protect your iron and board) the children can add more color if it is not dark enough. Then reiron.
These are fun projects to do. I am working on a pillow now where I outlined embroidered the design and colored the inside parts.