Learn how to make a crossbow out of easily available household/office items- not least of which, a ruler! Why only use a ruler to measure stuff? Turn it into a weapon instead!
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Materials
The things you'll need:
A Ruler (steel, wooden or plastic- I happened to have steel)
Two unsharpened pencils (or something of equal length like disposable chopsticks)
Rubber Bands (amount depends on how tense you want the bow)
Strong Tape (I used 3M brand clear duct tape- strong glue may work too)
A drinking straw
Medium sized Binder Clip (wide enough to fit over the end of the ruler)
3M Wall Hook things (as a handle/grip)
Bamboo (Shish Kebab) Skewers (for arrows)
Step 2: Construction of Bow
Step 1: Tape the two pencils together. Make sure you leave either end of the pencils
untaped so you can can get the rubber bands between the pencils later
Step 2: Tape the two pencils to the top of the ruler so they are perpendicular to each
other- like a cross without the top.
Step 3: Rubber Bands
Step 3: I used four rubber bands, but looking back I probably could've done it with two
and gotten more power. Anyway knot the bands together as shown in the
Step 4: Attaching the Rubber Bands
Step 4: Slide one of the double over bands between the two pencils at one and tape in
place. Do the same with the other end.
Step 5: Final Touches
Step 5: Cut a small length of the drinking straw. (not too long or the bands will catch on
the straw and therefore decrease the amount of power. Tape the straw piece to
the ruler near where the tip of you arrow will rest when loaded.
Step 6: Take the 3M Wall Hook thing and attach it to the underside of the ruler (hook
end facing you) to use as a handle/grip.
Step 7: Put the binder clip on the end of the ruler. If your ruler is steel/metal. the clip
may slide around easily. Just add a piece of tape the part of the ruler where the
Step 6: Load and Fire Away!
All Done! You're ready to fire away! Don't fire at anyone though. You could skewer someone's eye.
Notes on loading. It may help to wrap a bit of tape around the middle of the bands to
aid placement behind the arrow.
Load the bands first. Pull the bands down and into the clip. Then
insert the skewer arrow through the straw and push into the binder
Fire by simply squeezing the binder clip ends.