I my opinion, weight training is absolutely essential to improvement. If your season is only three months long, then you should look at whether you're really into seeing your athletes improving. We're all different, but the athletes that want college paid for are not three month athletes and neither are their coaches. Seasonal coaching is great for recreational programs, but the results we have had (six state titles in nine years) came as a result of putting in time in the weight room. It will involve you a lot more, because given your time with the team, your athletes probably love running for you. I would just say don't leave it to a school weight training class to get your athletes to their next level.