Hello D. J.
You asked about buying wire with someone for a better discount on
supplies for a kids' jewelery class. I've taught a couple such
classes (2 hours, one meeting), and although I give the kids about 4
feet of 22 or 20 gauge sterling wire, I also give them a few feet of
copper wire from the hardware store, in the same gauges. They
practice using the copper wire, then advance to making their final
project with sterling. That cuts down on the need for so much silver
wire, and reduces costs.
You don't say if this is a single class or a series, but an ounce
each of the wire gauges you mention will surely provide enough for
several students. You can do the math, but I suspect that what you
save by combining orders with someone else is likely to be eaten up
by the expense of sending your materials separately to you.
Good for you in volunteering your time and knowledge to teach the
Judy in Kansas