Tape a piece of plastic wrap to a pencil. Walk around your neighborhood. Note the different wind speeds in different locations.
Push a thumbtack into the eraser of a pencil. Tie a piece of thread around the thumbtack. Hold the pencil in the air and watch the wind blow the thread. Take note of the angle of the thread. The more horizontal the thread, the greater the wind energy.
Punch a hole in each of four paper cups a half inch below the rim. Punch four equally spaced holes around the fifth cup and one hole in the center of the bottom of that cup. Push a soda straw through the hole in one of the four cups. Fold the end of the straw and staple it to the inside of the cup across from the hole. Repeat procedure for another one-hole cup.
Slide the straws of the stapled cups through a hole in the cup with four holes until they come out through the hole on the opposite side. Connect the remaining one-hole cups to the straws. Align the four cups so that their open ends face the same direction.
Push the eraser end of a pencil through the hole in the bottom of the center cup. Push a pin into the end of the eraser. Calculate the velocity your anemometer by calculating the number of revolutions per minute. The anemometer is a vertical-axis wind collector