Green Screen PSA for OSU bike riders safety

Currently I am in a studio production class at OSU. This video was for an assignment to make a psa about bike riders safety. As you can see it does not look very realistic at all. In fact its some of the worst green screen work I have seen.  But It was a fun thing to shoot and I have to say I learned a lot of what to do and what not to do when making a video using green screen. 
NUMBER 1- Lighting is EVERYTHING!    if the green screen is not lite completely evenly then the chroma key process will be pretty rough. (since some greens were different shades of green I can not key out the color correctly.
This project has got me thinking though. I want to set up my own green screen and do some fun independent projects working with chroma key effects
UPDATE:  I got smart and changed some settings. the original green screen is bad enough that I cant completly fix it but here is another version of the video for fun.