I found this cute and easy activity on the Lost Button Studio website.
It's a good project if you have scraps of leftover cardstock/heavy paper, which I always do.
My Grade 1 students used neon oil pastels to draw patterns and designs on the card,
then did a watercolour wash over the top.
You always gets 'oohs and aaahs' from the little ones when they see the oil pastels resisting the paint. Let dry, laminate, punch a hole at the top and add some yarn.