Set this fun experiment up with plastic cups, plastic egg cartons, or plastic pot trays. Either set out baking soda in small bowls or containers with spoons or scoopers, or have the baking soda alread
Set up the full table with wax paper taped down, or set up individual spots. Set out cups with colored water (food dye) and droppers. If you are worried about spills, put these is paint cups with lids
Using the print out as a guideline, either make your own arches out of dough or cardboard, or just cut out the arches. You can color these to be in rainbow order or leave blank. Let the children play