Tomato Egg FTW
Fried rice? or Fried pancake is a good one.
Steamed fish with oil garlic and soy
Congee

Why don't you try and make some dumplings, go down and watch how they make them and then try doing it yourself. Mostly, to cook them you need a steamer. Usually if they fry them, they steam them first. It looks easy enough to me, so you should be able to do it.
If you want to make Chinese dishes you have to have the sauces, more so than the ingredients, as the sauces make the dish, the ingredients are usually available anywhere. Try and find them in your local China town store, if not take some home, make sure they are un-opened and sealed, so you can get through customs

do jiao... you know that green bean, garlic, bacon thing? That

I think the easiest would be hot pot.

Buy a pouch of hot pot seasonings, go back home and get a nice selection of meats, veggies, etc. Tons of stuff is also available from Asian food markets depending on where you're from, or just bring back some dried stuff (doufu pi, etc)

Set up either a hot plate or a crock pot, or if you have a small gas burner stove (which you can buy at camping shops), put a pot on with the spices, have everyone load in the food and dig in.

Really easy and difficult to mess up!

This is nice because not only do they get to try perhaps a Chinese style food they might not be familiar with, they can also get the experience of how people like to eat here.

cook anything with loads of oil leave in the bathroom next to the toilet,for 5 to 6 hours will be very authentic

There are some very basic soups as well if you're in that kind of thing - egg and tomato soup.