I will start with the obvious intervals, I prefer Timmons, but others like Tabata, sprinters like you will probably be equally suited with either.
Plyometric training to give you more explosive power. Keep this sensible due to your age, masses of impact on still growing or unfused bones is not recommended so keep this as a small part of your training.
Explosive weight training. This will be best suited as compound movements, many sprinters use Olympic lift style training for the explosive nature. This comes with a major health warning, be 100%+ sure that you have the technique perfect with a pathetic weight (this could be a broomstick) before considering doing this with higher weights. As with anyone your age keep weight training sensible, reps of 10 or above unless you have a coach who can assure your safety in lower reps and at your age 10 reps should be on weights you could do 11 or 12 with, training to failure while still growing should be for extreme reps only 50+ when this is fatigue not stress.
Examples of these exercises are high pulls, power cleans, snatch, push press, clean and press and jump lunges. They use a lot of the body and done wrong you will injure yourself in multiple places, but the advantages gained from being able to do them well on your overall power and co-ordination are worth the effort.