You'll need:

• Large plastic cup
• Masking tape
• Paper
• Rocks
• Straw
• Pencil
• Straight pin

Instructions:

1. Cut a circle out of the paper that is larger then the opened end of the large plastic cup.
2. Fill the bottom of the cup with some rocks.
3. Put the paper circle over the open end of the cup and tape it around so the rocks remain in it when inverted.
4. Poke a small hole in what is now the top of the cup. (what is normally the bottom)
5. Stick the pencil in the cup with the eraser end up.
6. Cut two small triangles out of the left over paper.
7. Make a small slit in both ends of the straw.
8. Slide the triangles in the slits so it looks like the straw has an arrow on each end.
9. Poke the straight pin through the middle of the straw and into the eraser of the pencil.
10. Place in the middle of a field and watch the straw spin around according to the directikon of the wind.