1 hour fartleks the day before a meet is questionable even for 5000 meter runners, I don’t see the benefit for sprinters at all. Fact is, I don’t know if 1 hour fartleks are very helpful for sprinters at any part of the season or off season.
I’d do what you can to change the coach’s opinion. Send them to this site. Even buy the video and DVD for your coach if you can afford it. See if the school will pay for it.
Print out articles and bring it to him.
If all else fails, try to find a track club in the area. If it’s any good, quit your school team and join up.