Sorry.... I can't edit the post below....
EDIT: my calves and side of calves look a d are stronger after 6 months vs 30 years of running.
Also, track ends... Kids should take 2-4 weeks off of running completely. Then, very easy running 5x/wk...3-5 miles (very easy running). That will build over the summer. But just long slow distance.
Add the lifting when that 5x/wk running is occurring and keep it through summer (lift 2x/wk). Then when season starts, make adjustments. Prob have to go to 1x/wk lifts (Tuesday?... Races on Saturday). And begin introducing speed work to peak at end of season meets.