i did census work last year. the trainings are a week long, and are done at a 6th or 7th grade level (at least that's what we were told). this was is a good thing, as during the 2000 census they had a hard time recruiting people. the majority of my training group had college degrees, and we spent 4 days learning how to use a hand held gps device - it was rather mind numbing!
one of the things i had to do was delete addresses that had been verified as duplicates or invalid - i had my 3 year old doing it for me! she had to push three buttons, and she can't read, so i really wasn't violating anyone's privacy!
our group was supposed to work 14 weeks, then it ended up only being 6 weeks. my sister just did the week of training, taking a week off her regular job, as i had to. she only ended up working that job for 2 weeks!
i would have gone to do more, even being 7 months pregnant, if i didn't have to take off of work for a week of training.
if it's not too big of a hassle for you to do the training (which i guess has to be redone for every job), and you don't have to worry too much about child care, i would say go for it!
its something that i wanted to do just to be a part of it, as the census is a big deal. it was nice to have a new experience and make a little money, too. people were nice, for the most part - and this was before the big ad push - and those who were a little weird just gave me a few good stories to tell!