I can't' believe it's earth day tomorrow. I thought I would highlight I've done in the past. It's super easy to do and you only need a few (very inexpensive) items.
You will need:
blue and green markers
water in a spray bottle
Start by drawing in green and blue with the markers on the coffee filters.
Any pattern, blob, shape, is fine.
Then spray it with water. The marker will spread and run to cover the filter.
Leave it to dry. Or if you are in a hurry, dry it with a hair dryer.
Once it was dry we glued it to a piece of construction paper.
I then had the kids write the words "Earth Day" on it
For children who have trouble printing, I made some words that you can print out, have them colour, cut out and glue on their page. You can grab them for free by clicking on the picture below.