To OP:
It does depend on your current PRs to some extent. However, don't worry about easy day pace. If you can talk and you don't have to think about the pace on your easy runs you probably aren't going too hard. The key is to recover after workouts and races so if you are close to 8min pace some days don't worry that it is too slow.
I was running about 50mpw as a junior in hs so I can kind of relate to what you're going through.
If you are thinking short term, yeah you can go out and hammer and push both mileage and intensity...you would probably improve initially also - however, you will most likely get an injury or become overtrained after awhile.
Think long term, and you can slowly increase your mileage...maybe up to 60-70mpw for your senior year. In this case, you don't push the intensity of your easy days....if anything you go slower until you fully adapt to higher mileage.
Structure in a long run of 90min or more on the weekend or when you have time if you can.
Of course all this depends on what other types of workouts you are doing? Tempos runs, long interval workouts and short, alactic sprints/striders are the way to go in terms of long term success and strength. Also depends on what event you are focusing on racing - I assume mile/2 mile?
The hard days and easy days only balance out well and stimulate ideal adaptations if the right systems are stressed at the right time and the body can supercompensate.
good luck!
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