Three scientists creating a Balloon Rocket

For the Science fair Jess, Braeden and I did an experiment called Balloon Rocket. I think that we worked together great because we didn't talk too much. The experiment worked out well but the little balloons didn't work. The normal balloon went the furthest and fastest along the string.
Here is a picture of our science board.

Here is a video of our experiment

This is of the double balloon that didn't work very well.