Pasta for 70

What kind of equipment do you have access to?  A commercial tilt skillet?  Commercial steamers?

Well looks like you'll be cooking your pasta in quite a few different batches so first of all remember to change your water every batch or the starch will get out of control in a hurry.  You shouldn't need to parcook the pasta much if at all so when its finished, rinse it with cold water to stop it from cooking, toss with olive oil to prevent it from sticking together or drying out, and store it in whatever containers you'll be using to move it.  You'll want lids or plastic wrap over those.

Toss your pasta with the heated sauce once you're at your location.  If you don't have chaffing dishes to keep your buffet warm, don't be stingy with the sauce.  Assuming the sauce isn't so hot as to be inappropriate for serving to kids anyways, it shouldn't be a threat to overcook your pasta.

Posted by GInger V1 

Oh dear God, no.

BDL

You don't want to cook it in the sauce at all, rather use the sauce to reheat it.  Cook it al dente, and rinse it with cold water to keep it there.  Remember this is for kids which means overcooked pasta is much better than undercooked.  They're used to spaghetti-O's.

If you can't cook there, fully cook it wherever you're going to cook it; drain it into the hotel pans, and sauce immediately.  Reheat on site.  Plan on refreshing the sauce in each pan with a little, lightly-salted hot water.  Just enough to make the pasta seem saucy.

In the first place, reheated, sauced pasta is GREAT!!!  (Surely, you like leftover spaghetti!)  In the second, pre-cooked, un-sauced pasta doesn't keep or transport without sticking together in ugly, pasty, unappetizing clumps, unless you coat it with TONS of oil (in which case it's sauced -- but in oil). 

If you want to treat the meatballs extra gently, you may transport them in their own separate pans (in a little sauce); reheat them separately and either add at the last minute or serve separately.  Serving the meatballs separately allows better portion control, and more attractive plating.  To my mind it comes down to whether you have enough help to staff a buffet line and help with portions, or are just going to let the diners fend for themselves.  Make it as easy as you can on yourself.

It's only pasta and meatballs.  Cook more than you think you'll need.  If the pasta is the main course, the sides are tossed salad and garlic bread (been there, done that), and the diners are primarily adults, figure four covers per pound of pasta -- max.

I suspect you already know all of this, but are intimidated by the quantities and responsibility.  Think of your event as a pot luck, stay out of the cooking sherry, and you'll be fine.

BDL

Are there even hotel pans?  What are the options for heating/cooking onsite?

Since for kids does not have to be boiling hot. 

Precook pasta al dente  cool toss with a bit of oil.

At the site  bring sauce to a good hot simmer with meatballs in it.

put pasta in a pot UNDER HOTTEST TAP WATER AVAILABLE  let  sit a while till hot drain well top with sauce and meatballs in chaffers

Cook pasta completely before dont cook it in the sauce.  Salad and plenty of bread if kids. Don't forgrt grated cheese. Bring 1 or 3 boxes raw pasta with you in case count goes up, or they eat a lot

Take it out of fridge well in advance otherwise it will make sauce and meatballs ice cold. Pasta will last outside at room temp at least 6 hours so don't worry about it going bad.  Good Luck

Another option for you is to do a baked pasta dish.  Cook the Rigotoni a slight more al dente than you normally would.  Mix with ricotta, parm, maossarella and your sauce with about the same ratio as you would use for lasagna.  (I like mine a little wetter and it bakes out)  top with mozzarela and throw in the oven to finish.  Serve the meatballs on the side with some extra sauce.

This approach greatly reduces the issues with doing pasta for so many people.  And, in my experiece, people love the dish.

Never wash pasta with water. If you do, youre washing away the glue(starch) that it needs in order for the sauce to stick to each individual pasta piece. Cook everything right before service and transport it.

Put your bags into hot water, then plate > sauce > serve. Fixes your presentation problem.