How do I make a small self propelled boat? !!!!!!!!!!! : S it's for school?

Question

For my physics class i'm supposed to make a self propelled boat because all classes are going to be in a competition. The key is for the boat to have speed. I wonder if anybody can tell me how to build an inexpenssive and effective toy boat that will move in a straight line and be fast. thank u

Answer 1

Inexpensive?  Without knowing the dimensions or propulsion perimeters in your question. I would guess you could take an oversize tupper wear container w/ a lid and cut a third of it off on each side, save the middle section w/ lid to cut out a rudder and keel later. (w/ scissors)

   After sanding edges,join both 1/3 bowl pieces together w/ (hot glue) or (liquid nails) making sure that lid halfs can be removed from the body so you can access the inside, attach keel  parallel w/ bottom of the boat, on seam - then attach old house or car keys to this piece for bouyancy stabilization. use  rubber bands. (don't glue keys on yet)

  Next drill or burn a hole through the forward top and bottom back of the boat at a shallow angle. Attach a solid plastic twistie straw (with which air will pass through from a balloon at the top) and glue in place in just the bottom hole.

  And (or) hot glue 2 solid stiff rudders on the back of the boat 3to 4" apart ,making sure they're equally placed from center.      

   Staple 1 rubber band across  them so it's stretched just below the water line and staple a  piece of plastic or wood that will spin when wound up.  Make sure this piece is perfectly centered on the rubber band. Test and adjust keys to make balance better. Finally  finish w/ a thin red stripe around the lid line (finger nail polish) and fit a balloon to straw end at top.