One year in Bible School we did flower pounding. I made muslim totes - about 10" by 14" - and then had the kids slip magazines in the tote so when they pounded the flowers, it wouldn't bleed thru the fabric. I asked for church members to donate flowers and the use of their hammers. Some kids planned a design and some designs looked like weed gardens. But they had a ball! I think I had them lay a couple layers of papertowel over the flowers before pounding, and then had them iron the completed picture. This was a cheap and fun project!