Generally during the summer and winter, you want to build your mileage base for the next season.
I've written a schedule for myself for the winter break, and one for females as well.
Each day the runner should lift weights and keep their upper body in shape, toned, not building a lot of muscle.
Boys
Saturday - Dec. 23 - Long run 8-10 miles or 70 minutes group run
Sunday - Dec. 24 - 6 miles or 50 minutes on your own
Monday - Dec. 25 - Christmas OFF, or run your own recovery run
Tuesday - Dec. 26 - 8 miles or 55 minutes on your own
Wednesday - Dec. 27 - 8 mile or 55 minute fartlek, 3 minutes fast pace, two minutes recovery pace group run
Thursday - Dec. 28 - eight miles or 55 minutes group run
Friday - Dec. 29 - 8 miles, 2 mile warm up, 4 mile tempo (steady state, keep the same pace for four miles), two mile warm down on your own
Repeat workout for next week, new years off/recovery run
Girls
Saturday - Dec. 23 - Long run 6-8 miles or 55 minutes group run
Sunday - Dec. 24 - 5 miles or 40 minutes on your own
Monday - Dec. 25 - Christmas OFF, or run your own recovery run
Tuesday - Dec. 26 - 7 miles or 50 minutes on your own
Wednesday - Dec. 27 - 7 mile or 50 minute fartlek, 3 minutes fast pace, two minutes recovery pace group run
Thursday - Dec. 28 - 7 miles or 50 minutes group run
Friday - Dec. 29 - 7 miles, 2 mile warm up, 3 mile tempo (steady state, keep the same pace for four miles), two mile warm down on your own
Repeat workout for next week, new years off/recovery run
This should build a runner's base up, and make longer runs less challenging. After break, start doing some intervals and do slowly put faster track workouts into the schedule. This should build a runner for track and help them become efficient from the 800-3200 meter runs.

