Going into high school cross country, you'll want to be careful not to take-on too much mileage too soon. The largest factor in training is your history - how many consecutive months you have actually been training in the last two calendar years. And by training, one must question the quality of training within your previous middle school program. If you are coming from a program without much guidance, thus not much actual training in the form of tempos, intervals, hill repeats, steady runs, etc., then you'll want to consider a very conservative approach to reduce the chance of an overuse injury.
June: Begin June with the simple two days each week with Whisper. If you were able to attend the two days in the pool that consisted of aqua-jogging and cross-training, then you'll likely get over the initial soreness faster than those who were unable to attend. Regardless, consistency is essential, so running twice a week with Whisper can really help with the beginning steps of creating a base for July.
July: In early July you can add a third day of running 25-30 minutes on your own (outside of Whisper - with your HS program or with friends), then by late July be up to 30-40 minutes on that third day. Between the practices at Whisper and the third day, you'll accumulate 15-18 miles in a week. The pool workouts will be you bodies best friend. Here, you'll circulate blood flow to all of the sore areas, promoting healing and recovery. Win-Win!
August: Once August arrives, you should be ready for a fourth day of running. The third day should remain at 30-40 minutes, and the fourth day should be 20-30 minutes, again depending on your history - be conservative, humble, and smart.
These runs on your own should be steady runs and nothing extreme, like intervals. Keep them low-key, fun, and with your teammates. It might also be a good idea to alternate days of wearing a timing watch one day, then not wearing a timing watch the next.
If you experience soreness that seems to not go away, then consider taking an extra rest day, or backing off on the fourth run (reducing the time on the fourth run). For example: if you run Monday, Tuesday, Thursday, Saturday, and you're achy on two consecutive Monday's, then back-off on one of the previous runs, yet still aiming for four runs in a week. Of course, this advice is provided you have a solid pair of running shoes that are "Coach Approved."
Most importantly, never hesitate to contact Coach Dave if you have any questions about your preparation for the season ahead..