Mixing running with lifting

Coach -

I'm the boy's head track coach at our middle school. I would be very interested in any ideas you have about how you organize your practices. We don't have a track, either.

What kind of workouts do you have for the various athletes (sprinters, distance, throwers, and jumpers)?

This will be my third year as our track coach. I threw shot and discus in high school (never very far!), but beyond that, I really don't know much about T & F.

My approach to T & F is basically the same as yours - I encourage my 8th graders who will be playing football for me the next year to go out for track more or less for conditioning.

Govertical - I am in a hurry so this might not make sense.
We start with a warmup run (afterwards the boys can static on their own if that's what they want to do).
Then we go to dynamic stretch / form run.
From there we will either do plyos and / or a speed workout (short sprints on the fb field or gym). Everybody does these together (throwers, distance and sprinters). I feel like this is the most important thing considering we are trying to make better football players, and you have to have good speed / explosiveness to be good at any event in Track and field.
We alternate the plyos/speed with core (abs, perfect squat, perfect pushup, clap pushups,etc) every other day if possible.
Depending on the day, we will try to break up and do individual things. A lot of the time I make the throwers do the sprint workout. It is tough, but that's good for them. A good part of the time though they just go throw if they are strictly throwers in competition.
Most of our track workouts take place on the block behind the school. It is about 540 meters long and has one corner with a decent incline. By running three sides of the block, we can run a quarter (approximately). I like (they hate) to have them end on the incline. I can see them start down the block as I stand on the incline. If I want the "super short sprinters" to run shorter while the middle and long distance are runnning quarters, they can run 120s coming at me. When I'm by myself, this is what I do a few times.
When in doubt and I really want to get after everyone, they all run quarter, 200 or 100 repeats. My feeling is that if you have a lot of people that can run quarters and halves, you will have a good team and your guys will be able to run a lot of races (shorter and longer). Sorry, kind of got off there.
My favorite workout is the hill workout. We live in a hilly town. Sometimes on Fridays when I'm going to a a clinic or something we will go in the morning. We start at the school and run to the hilliest part of town (not quite a mile). From there we run up the mother of all hills 3-5 times (it is about 300 meters). They have to keep their feet moving on the way back down, no matter how slow it is. We'll finish up with a few shorter sprints, then jog back to the school. I can keep a pretty good eye on everybody, and I can actually run it with them.
Not sure if this is what you were looking for.

Lochness,
What about say running repeats of 200 or 400? How do these affect the CNS? These are very demanding, but aren't necessarily "sprints?" I think I read the rule for intervals was 75 percent or less? 75% of what exactly?

CUI and CoachJD -

Thanks for the information.

This past year, we put a $75,000 fitness center in at the middle school. The PE classes use it, but I am going to implement it into track practice.

It is not free weight equipment (it's called Freemotion - kind of like really expensive Cybex gear), but it is better than nothing at all.