You can make see-thru planters from the 2 liter bottles. You cut them and use the bottom half, you can poke a few hole in the bottom, for the water to run out. You place an old saucer underneath the bottles to catch the run-off from the soil. The other is a catch game. You use the the top half of the bottles you cut. You need about a 18 inch piece of kite string or similar string. Glue one end of the string to the inside of the cap, you made need to glue a small round piece of paper on top, of wear you glued the string to hold it in place.Let it dry. Cut a hole near the neck of the bottle, Tie the other end of the string through the hold you made and through the opening of the bottle.
Hold the bottle by the neck, with the string at the back of the bottle. Flip the bottle up and try to catch the cap in it. Small kids, see who can get the cap in the most. You can decorate the bottle, and make a variation of the game. You can also hold the the bottle half by the neck and spin the string around, like a helicopter.