Some of the KidWind kits include a wooden spool to do a weight lifter activity. While Vernier does not sell wooden spools as a separate item, they are included in the following items:

KidWind Basic Wind Experiment Kit (KW-BWX)
KidWind Basic Wind Experiment Kit (KW-BWXC)
KidWind Advanced Wind Experiment Kit (KW-AWX)
KidWind Advanced Wind Experiment Kit (KW-AWXC)
Drivetrain Set (KW-DS)
Advanced Wind Experiment Kit Nacelle (KW-AWXN)

If you find that you need extra spools, you will want to make sure the holes in the spools are 3/8 inch diameter.

We recommend looking for spools at craft stores such as Michaels or JoAnns. If you need to purchase online, we found these spools that will work:

http://www.craftparts.com/ item number SP9000