Don't worry if you don't have a chemistry lab. These projects use materials you can find around the house.
1. Make Slime
Anne Helmenstine
You don't need to have esoteric chemicals and a lab to have a good time with chemistry. Yes, your average fourth grader can make slime. That doesn't mean it's any less fun when you're older.
2. Borax Snowflake
Anne Helmenstine
This is a crystal-growing project that is safe and easy enough for kids. You can make shapes other than snowflakes, and you can color the crystals. As a side note, if you use these as Christmas decorations and store them, the borax is a natural insecticide and will help keep your long-term storage area pest-free. If they develop a white precipitant, you can lightly rinse them (don't dissolve too much crystal). Did I mention the snowflakes sparkle really nicely?
3. Mentos & Diet Soda Fountain
Anne Helmenstine
This is a backyard activity, best accompanied by a garden hose. The mentos fountain is more spectacular than a baking soda volcano. In fact, if you make the volcano and find the eruption to be disappointing, try substituting these ingredients.
4. Penny Chemistry
You can clean pennies, coat them with verdigris, and plate them with copper. This project demonstrates several chemical processes, yet the materials are easy to find and the science is safe enough for kids.5. Invisible Ink
Invisible inks either react with another chemical to become visible or else weaken the structure of the paper so the message appears if you hold it over a heat source. We're not talking about fire here. The heat of a normal light bulb is all that's required to darken the lettering. This baking soda recipe is nice because if you don't want to use a light bulb to reveal the message, you can just swab the paper with grape juice instead.6. Color Fire
Anne Helmenstine
Fire is fun. Colored fire is even better. These additives are safe. They won't, in general, produce a smoke that is any better or worse for you than normal smoke. Depending on what you add, the ashes will have a different elemental composition from a normal wood fire, but if you're burning trash or printed material, you have a similar end result. In my opinion, this is suitable for a home fire or kid's campfire, plus most chemicals are found around the house (even of non-chemists).
