Supplies:

• Two plastic soda bottles (2 liter or 20 oz. — do not use glass)
• Water
• Food coloring or glitter (optional)
• Tornado Tube bottle connector OR duct tape

Instructions:

1. Fill one of the soda bottles 2/3 full of water. Screw the Tornado Tube on to this bottle. (If you don't have a Tornado Tube, have an adult drill a 3/8" hole in the two bottle caps and put them back on the bottles.) For fun, you can add glitter or food coloring to the water.
2. Attach the other empty plastic soda bottle of the same size to the other end of the Tornado Tube. (If you don't have a Tornado Tube, secure the caps together with duct tape.
3. Rotate bottles so that the full bottle is on top. Do not tilt it. With your hand firmly on top of the full bottle, shake the upper bottle in a circular motion. A mini tornado will form.

Try these variations to see how it affects the strength of your tornado.

• use hot and then cold water
• increase the pressure in the bottles by squeezing them
• change the amount of water
• change the type of liquid in the bottle