Guest Post by Andrea Erins

1. Mentos & Coke Geyser – This experiment has spectacular results, but you might want to perform it outside to avoid making a mess. Open a new 2-liter bottle of soda, then drop a whole roll of Mentos mints in at once—the best way to do this is to put all the Mentos in a roll of paper that you tip into the bottle mouth. Once you put in the Mentos, stand back and watch the explosion!

2. GAK – Kids love to play with this mystery substance, even when the experiment is done! Mix ½ cup of warm water and a teaspoon of Borax. Pour an 8-oz bottle of Elmer’s glue in a bowl and then gradually add the Borax solution. It’s easiest to mix with your hands. When it’s all mixed together you have slime!

3. Make Your Own Lava Lamp – Fill a plastic soda bottle ¾ full with vegetable oil, then fill the rest of the bottle with water. Add some drops of food coloring (it will only color the water). Then break up an Alka-Seltzer tablet into about 8 pieces and drop in a piece. When the bubbling stops, add another piece, until all of the pieces are gone. Screw on the bottle top and move the bottle back and forth to watch the “lava” move around.

4. Tornado in a Bottle – Fill a 1- or 2-liter plastic soda bottle to the top with water. Duct tape another bottle of the same size to the first bottle at the open end. Turn the bottle-tube over and watch a tornado vortex form as the water pours into the bottom.

5. Color-Changing Milk – Pour some milk on a dinner plate or in a shallow bowl. Put four drops of food coloring in the center—one of each color—so that there is a little space between the colors. Put some dish soap on a cotton swab and then dip it into the water, holding it there for about 10 seconds. The colors will burst and swirl because of the soap’s effect on the milk.

6. Squeeze Egg – This experiment is simple but amazing. Take a raw egg in your hand and wrap your fingers around it. Squeeze it with even pressure – it won’t break. The strength in the egg’s curved design keeps it from breaking, unless you put pressure on one specific point.

7. Hovercraft – Cut out a 4-inch square of cardboard and punch a hole in the center. Glue a thread spool to the cardboard so that the holes line up. Glue a circle of paper on top of the spool and punch a hole through it. Blow up a balloon and twist the end, then stretch the mouth of the balloon over the spool. While still holding the balloon, set the whole thing on a level table and let go!

8. Fruity Electricity – The chemicals in batteries contain electrolytes, which help electricity to flow through the electrodes in copper and zinc wires. Make an electric circuit with light bulb and a fruit as the battery. Children could try different fruits to see which work best (citrus fruits are the best because of the citric acid).

9. Grow Rock Candy – Tie thick string to a pencil or popsicle stick and set it over the top of a glass jar. Make a saturated sugar solution by gradually adding sugar to boiling water until the sugar won’t dissolve anymore. You may want to add food coloring. Pour the solution into the jar and wait a few days to a week until the crystal is grown.

10. Volcano – This classic experiment never gets old! Use a funnel to pour a cup of baking soda into a plastic soda bottle. Then mix a cup of vinegar with some dish soap – you may also want to add glitter and food coloring. When you pour the vinegar mixture into the bottle, watch it erupt!

Andrea Erins has been a college professor for 13 years and likes to write about various topics related to education. She is the owner of the site Masters in Education Guide.