If you have a pool in your backyard, drink water out of a water bottle while underwater!!
Take a plastic water bottle unscrew the cap and ask someone to look in it and tell you what you see. When they look at the water, squirt the bottle really hard into their face
Empty a bottle of Windex, wash it out, fill it with blue Gatorade and walk down the street drinking it.
Clean out a mayonnaise bottle and replace it with yogurt. Then, bring it to lunch at school and start eating it.
Go to a grocery store with a bottle of spray disinfectant, follow some one around and spray everything they touch.
Freeze water bottles and cut off the plastic and use the water bottle shaped ice to use as a bowling ball to throw down the hallway in your dorm hall.
Fill a water bottle with sugar poke holes and add a string to it hang it upside down and watch the humming birds.
Go for a walk with a squirt bottle and every time you see someone smoking squirt them with water.
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