You need:
Sculpey clay or similar
thin twine
sticks cut to 12"-14" size
nature or themed findings to press into clay
oven
acrylic paint and brushes
individual damp paper towels
damp rags for finger and table clean up
covered work surface
This is a 2-3 day or 2-3 session project, to allow for time to bake the clay pieces and do the tie on process.
Our Bible School theme was Noah's Ark (ocean), so we made clay "charms" to fit this theme. Each student got 5 pre-cut clay pieces. They need to work the clay (squish and roll each piece until smooth and warm) before forming it so it does not crumble. I usually have them do this while I demonstrate any tips or techniques they need to make the craft.
I collected items to fit the theme: in this case, real and plastic shells and some old shell shaped beads I had in my stash.
I was copying this nature themed "wind chime" I made last year. After softening and working the clay, each piece is flattened slightly and an imprint is made with the chosen object. I usually have paper plates for each student to work on to keep the table clean. Label plates with each student's name to help keep projects organized. Poke a hanging hole at the top of each clay piece. I usually check and enlarge these holes to acomodate the string we are using. If any holes are too small after baking, a drill can enlarge them too.
Bake clay, following package directions, and cool. Apply acrylic paint on one or both sides of the clay. Before it dries, wipe most of it off, leaving the deepest color in the indentations. Sometimes it takes a couple of tries to get this process right. It's OK to re-paint and wipe again if too much comes off. (it might be a good idea to do a test run at home first so you can advise and show the process.) I make sure each student has a damp paper towel for this. I also have damp rags placed down the middle of the table for strategic finger and table clean up. After each one is done, allow them to dry on the paper plates.
I pre-cut strings for hanging, or you could let the kids do this if they have the time and skill. Tie the clay pieces to the string and hang them from a stick at intervals. Add a looped string at the top of the stick at the fulcrum point to balance. Hang and enjoy.The nature chime that I made hung out in the weather for a year and retained the colors.