Brain Pop:  Levers and Inclined Planes
Wait for the ad to finish loading, then play the movie and take a quiz about levers.  There is another movie about inclined planes.  Without a subscription, you can only watch two BrainPop movies a day from the same computer.

Dirtmeister's Simple Machines
Once you know about the simple machines, come to this site for forms to fill out for observing a simple machine and writing a report. You can read sample reports from students.

EdHeads: Simple Machines

Inquiry Almanack:  Simple Machines
Text and illustrations, plus demonstrations the you can do yourself. Check out the LEGO simple machines by clicking on "extra information" by most machines.

Leonardo's Inventors Workshop
Simple machines and other machines that Leonardo used in his inventions. Check out the "Gadget Anatomy" link to see if you can recognize what machines Leonardo used.  Can you figure out what each of Leonardo's machines does? Click on the red buttons to view his sketches. Choose an answer from the orange buttons underneath.

Marvelous Machines
This site lists hands-on activities and experiments for levers, wheels, and inclined planes.  It includes teacher notes, materials, and references.  Although designed for third grade, these activities can be adapted to other grade levels.

Simple Machines Learning Site
This site was set up by a graduate student to teach children about simple machines. Click on the machines to learn more about them.  There is an interactive quiz on the bottom of the page.  This site is no longer being maintained, but will remain online for the use of educators.  Most links to other sites are no longer active.

Simple Machines Lesson Plan
Teacher created lesson plans for teaching simple machines in grades 3 and 4.

Simple Machines Made Simpler
This colorful, kid-created, and musical site shows what students can do with the information they gather about simple machines from other references.  It is an example of integrating technology at its best.  One of the pages on the site shows photographs shot with a digital camera of simple machines found around the school.  There is also an interactive quiz at the end of the site. 

Simple Machines: MIKIDS.com
This clear and simple site has definitions, photos, and activities for each machine.  There are also links, a printable activity sheet, and an online quiz at the bottom of the page.

Simple Machines Yesterday and Today
A brief look at simple machines from the past and how they are used today. There is a mini quiz at the bottom.