No worries, that's definitely a reasonable impression since there are way more postgrads than undergrads. I just wanted to point out that undergrads are allowed to participate in the 'action'. But of course there is the occasional bad class (Peter Shor is not that good at teaching Shor's algorithm).
For what it's worth, the lab classes I attended at the public university in Texas I attended after one quarter at MIT was essentially... "here's the key to the lab, knock yourself out. come find me if you have questions." The only reason we didn't make an initiator in the lab that year is we couldn't find the polonium.
