depending on the number of boards to be manufactured, an “order pooling” service would be the right choice here? If the quantity is small, and the designs are in “popular” technology (number of layers, substrate type etc) it might be the best option here; you can save on shipping costs, but the unit price should be much lower than having individually manufactured boards (even if 2 designs combined into one, which the PCB manufacturers do not actually like and tend to charge more)
I like PCBWay for this very reason. You give them gerbers for a single board. They do a sanity check. If they find errors (eg missing edge cut), they tell you. Rinse, repeat. You can do this for as many boards as you want. When everything is ready, you give them money, they cut the boards, and they send them to you. If there is a problem, their default is to resolve the problem, finish the boards, and ship all as a set. I don’t have a lot of experience with multiple boards from other vendors, but I assume most will do the same.
@ SheldonNyce - how did this all turn out?
Making these kinds of mistakes are all part of the educational experience… and often the more pain, the more the lesson sinks in. In 5 years, the lesson will be important, not the specific grade in the class.