The story and animation are not that great. I just rate it so highly for the last few episodes.
Basically kagami can build a time machine (if he had the equipment) and go and do what he wants wherever he wants etc., but he ends up understanding that he can create his own future (and it be more interesting and rewarding) by improving the educational system/students (which currently is a memorizing institution. Not one that teaches you to think). This concept is exactly what I thought through grade school and even now. Our educational systems are crappy because of the monetary system that is out dated.
The rest of the anime is drawn out. At this point if you havn't started yet, I recommend watching it and just skipping through the boring parts. If you don't do that, you might end up dropping it and not getting to the good parts.