This past August, I took a 4-week course through Library Juice Academy that taught me different types of metadata as well as metadata schemas such as EAD, MOD, MAD, Dublin Core, and VRACore. I think that cataloging should be a required course in all library schools. Even if you never plan on being a cataloger or doing anything in technical services, it is vital to learn how a library works, in and out, I believe.
Alison Faith Young 