This is the best of the Water Balloon Launcher Lab videos. Using the original video and watching it in slow motion I was able to see the balloon after the launch in the air down the road (I've not been able to see it on YouTube, but if it is there it is around the 19th second, just after the bright flash and would be on the left side of the screen before the camera gets centered looking down the road). This is a lab that my physics students (all seniors) do to calculate the angle of launch of a projectile. Teaching and doing science can be a lot of fun. If you measure the time that it takes the balloon to travel and the distance it travelled horizontally you can calculate the horizontal speed (s=d/t). Assuming that air resistance is negligible and that the balloon reached the peak of its trajecory at the half-way point (in time) then the maximum height can be calculated using the free-fall formula (d=1/2*g*t^2). From there the average vertical speed can be calculated (s=d/t, using 1/2 of the total time). At this point trigonometry can be used to calculate the angle of launch (and Pythagorean's theorem can be used to calculate the average resultant speed).