I'm going to Disneyland!

I'm currently in charge of coordinating a trip to Disneyland for some past work associates. I work at a place called The Christa McAuliffe Space Education Center. It's set up as a Star Trek simulation where we take elementary students on Star Trek-like missions. The students staff the various positions on the ship (captain, first officer, weapons, etc.) and they decide what happens based on their actions. We currently have five ships and I'm the supervisor on the smallest one.

Anyway, two of my friends and I decided to take a trip to Disneyland this coming October. One of the other two going on this trip also works at the space center, and he boss found out we were planning this trip. He wants to go as well. But before I was even informed of this, two more staff decided that they want to come along. Now, suddenly the boss decides that we'll make this a trip for all of the adult flight directors (people over 18 who run the ships, we have some under 18).

So I'm in charge of setting up a trip for 12 people, for the least amount of money I can work out. I've gotten it figured out where we've got 12 3-day Disneyland park hopper passes, 4 hotel rooms (3 people in each), and airfare for all 12 for $350 per person. Who needs travel agents?