Geez,
I am completely sick of hearing people say they learn so much from instructing, that's a bunch of nonsense...
[font="]Ummm...if you aren't learning anything from being a CFI you are doing it wrong. I'd wager that in the 3 years I was a CFI my student taught tons of stuff. Not only about flying but about perspective, attitude (not in the A/C), personality, etc. PPL student are the most fun--sort of--teaching someone how to fly an airplane is a pretty cool thing. The excitement and nervousness of the first solo then the first x-country, first solo x-country, first written test, first checkride...you are setting their habit patterns for the entire future of their flying career.
Suck it up, teach with a better attitude, and start looking for things your students can teach you...with 750 hours you will most likely be out of there this fall flying something bigger and better.[/font]