Get the students to write down 4 things about themselves on a card that you hand out, then mix them up and hand them back, the students then have to find the person on the card. When they do they have to interview them and find the five things that are most important to them. Five is a good number because after the obvious things like my job, family, reading, we get onto more outlying interests.
For homework/ a written activity you could get the students to write up this information for you, so you can both check their written level at the start of term, but also keep this information to get to know your students better.