My routine goes something like this, you can change things based on the days in between starts.
Sunday- 7 innings 100 pitches
Monday- 30 minute run, total body lift, light throwing based on comfort
Tuesday- 10-20 minute run with some sprint jogs based on preference, ie run 10 poles then 10 60 yard dashes, throw medium distance up to long toss
Wednesday- Second lift, if needed, with lighter weight depending on when the pitchers is scheduled to go again, good long toss and or a bullpen session, make sure to lift after all throwing
Thursday- Sprints, 10-15 60 yard dashes any distance keep short less than 15 minutes
Friday- Pitch again...
These can be varied as i said based on how many days in between starts. I know for most college pitchers, they will start the same day each week which allows for more long tossing and a longer bullpen session and or one inning in relief after about 3 days of rest. Given that you are a high school coach you may have the kids throwing every five days or so. This is just a rough example of a possible program.