How to structure a tournament for knuckle heads

[HammerinHank]

I am hosting a tournament that we sold seats to at a school fundraiser. Can someone give me guidance on how to structure it? There will be about 30 players and most will have no clue what they are doing. We would like it to last about 3 hours and the tables we have can seat only 8 comfortably. The players will deal. The game is NLHE, of course.