Cup anemometers are simple instruments used by meteorologists to measure wind speed.  This set of instructions will guide you through the process of making a very simple anemometer using some common household products.

## Step 1: Materials needed

5  3oz. paper cups
2  Straws
1  pencil with eraser
1  push pin
1  pair of scissors

## Step 2: Making the central hub

Using a pair of scissors poke 4 evenly spaced holes around the edge of 1 cup. These holes should all be the same distance away from the edge of the cup. WARNING the pair of scissors are sharp be careful not to poke your fingers when making holes.

## Step 3: Adding the spokes

Insert the straws through the holes you just made so that the straws overlap in the center of the cup.

## Step 4: Adding a bottom hole

Make a hole in the bottom of the cup at the very center.  Make sure that the hole is the size of your pencil.

## Step 5: Creating the stand

Insert the pencil through the hole in the bottom so that the eraser is touching the intersection of the straws.

## Step 6: Adding the push pin

Poke your push pin through the two straws and into the eraser in the pencil.

## Step 7: Making the outer cups

Using the scissors make two holes in the remaining 4 cups. Make sure that these holes are opposite of each other and are the same distance from the lip of the cups.

## Step 8: Adding the outer cups

Place the onto the straws by threading the straws through the holes you just made in the cups. Position the cups so that the opening of one cup faces the bottom of the one before it.

Ten turns in one minute is equal to 1 mph of wind speed.  Marking the bottom of one cup will aid in counting the revolutions.
<p>wow&hellip; its awesome</p>
<a href="http://htr" rel="nofollow">great idea</a>
So is there any way to tell, without watching it, how many turns per minute it goes?
Like maybe a gear that had a notch with a button in a slot that when the wind blew it, the pencil made the gear move which was attached to another gear but when it hit the button it could be connected to like a computer or something and count exactly how many times the button was pressed? That seems a little advanced though :P
This is pretty neat. I never would have thought of this! Nice, coherent instructions too, much better than some other 'ibles.