Mac and cheese - 16 pounds dry pasta, 1 quart sauce per pound, 1/2 to 1 pound per pound of pasta
sweet potatoes - If whole baked, do about 120, split some. If casserole/canned, 6 #10 can or 42 pounds

baked chicken -
fried chicken -
This depends partly on what pieces. Basically you want about 320 pieces, divided into baked/fried according to local taste
boneless ham - 1 pound for each 5

salad - use the plan for 100 page, do 1 2/3 the amount for 100
rolls - 20 pounds, get good ones, 4-5 pounds butter

tea - 9 gallons, 2-3 not sweetened
lemonade, 8 gallons