This activity for a Halloween party is very fun and inexpensive, and your kids will like it. You will need baking soda, corn starch, vinegar, zip seal bags, orange food coloring for the pumpkin bombs, a marker and toilet paper. Start by drawing pumpkin and ghost faces on the zip seal bags. You can use a permanent marker and sandwich size bags. Larger bags will work too but you’ll just need more of the active ingredients. Now you can fill bags with the vinegar. Mix in a bit of corn starch for color. You can also add orange food coloring to the pumpkin bags. The rest of the tutorial is here.