First, congrats! This should be the trip of a lifetime for some of them.
With a group of 15, you may have to make special dining arrangements; if no one here on the boards chimes in with an answer, contact Disney BEFORE your 180 day mark so that you know in advance what you have to do.
That said, here would be my take on the restaurants:
50sPT - the group should have a good time here. You will most likely be split up into multiple tables.
San Angel - warning that this is true Mexico Mexican, not the Americanized Mexican food they may be used to. I'd make sure everybody in the group was on board with the menu.
Sanaa - definitely a more exotic choice. The location is lovely but most of the food is very Indian. If there are some picky eaters or some who might not be able to handle the spices, consider Boma instead. It is more African while Sanaa is more Indian, and as a buffet Boma has far more choices available. While there are authentic dishes, there are also enough basic things that everyone in the group should be satisfied. And as a buffet, you also get appetizers (salads, soups that are to die for) as well as entrees, sides, and desserts.
'Ohana - I think this is a great pick. Good food and lots of it, beautiful theming, and one of the best desserts ever.
Le Cellier - I'd think twice about this one. Next year it will be a Signature for both lunch and dinner; that's 2 TS credits if you're on the
DDP and $$$$ if you're paying OOP. In Michigan you're not that far from Canada so it's not all that exotic, and since you're a small school you're probably in a very rural area where people may be used to good home-grown beef so a steakhouse wouldn't be all that big of a deal. To stay in Epcot I'd suggest Biergarten or Coral Reef, or Cape May at the YC resort that's a short walk or boat ride from Epcot's International Gateway. Biergarten is well themed and is a German buffet. Buffets are good for hungry high-school kids and picky eaters seem to do really well with the food choices here. Coral Reef has OK food and a great environment since you watch the fish while you eat. Cape May is a non-character buffet dinner if the kids prefer to EAT the seafood rather than to watch it swim around; the highlight is all you can eat crab legs, as well as other seafood and non-fish selections.
