Tabata up the hill:
20 seconds sprint, 10 seconds walk back down the hill until you get to the top (about 700m) - took me approximately 4:17 to get to the top.

Jog back down the hill

Partner Sprints:
Sprint up the hill (to the tree, maybe 75M?) and back down the hill, rest while your partner does the same X 3
Run backwards up the hill (again, to the tree) and run forward down the hill, rest while your partner does the same X 3