Paul,
Depending on how you define a novice, yes, you can learn such a package's basic's in such a short time. BUT, imho, you will have to learn it by doing, using it in a job. The basics of 3D design are simple, but you will have to get them right before you can be of any use in industry. How to model a part, how to set-up an assembly (top down, bottom up), how to manage the files. You will know how to make a good drawing I presume.
The modern 3D packages are rather intuitive, so learning your way around is rather simple. As always with software nowadays, it's not the knowing 'how to', but the knowing 'what to'. If you know what you want to do, and know it can be done, most of the time you will figure out how to do it. The courses are mostly rather fast, with lots of examples, just to show you what the package can do, to get to know the method of operation. In working with the package you will master the things you have seen.
If you want to learn it on the side, I expect your company doesn't have a 3D package. I personaly think it isn't much use to fidle around in an illegal version at home, modeling your kids toys or something. You will lack the interaction regarding your work, will lack the challenge of altering your design. But if you want just a taste of the 3D-world, go for the cheap course. It will give you a good feel of what modern 3D packages can do!
Regards,
Pekelder
(Solid Edge, it's good, there are better, there are worse)