Screw be an appropriate choice. The left side pedal of a bicycle has a left-hand thread. More generally, screw may mean any helical device, such as a clamp, a micrometer, a ship's propeller, or an Archimedes' screw water pump. There is no universally accepted distinction between a screw and a bolt. A simple distinction that is often true, although not always, is that a bolt passes through a substrate and takes a nut on the other side, whereas a screw takes no nut because it threads directly into the substrate (a screw "screws into something", a bolt "bolts several things together").
Archimedes-lab.org and the development of creativity. Here's a quote from Scientific American (May 27, 2003): "This virtual lab borrows the empirical spirit and creative curiosity that Archimedes brought to his work and invites visitors to explore with the same expectations for mind-blowing discovery." Archimedes-lab.org has won several awards from scientific and educational publications, including a Scientific American Web Award in 2003, the National Council of Teachers of Mathematics Web Award, and a mention in MERLOT, the Multimedia Educational Resource for Learning and Online Teaching and in The DO-IT Center, the Disabilities, Opportunities, Internetworking, and Technology Center. Archimedes-lab.org Archimedes-lab.org is a free