I need some advice and shared skills for running tutorials.

I am given a list of questions, which the students also have and have two hours to fill.
There is about 20 in the group so I have been setting them off in groups then go round and basically find they are giving really rubbish/wrong answers and haven't done any reading, I try and correct them and get them to speak about more appropriate issues then move on to the next group, meanwhile I know most of the groups are drifting on to talking about "other things".

I'd like advice from people who have run these kind of tutorials to what should be happening and what works. Where I did my undergrad tutorials were two or three students with a lecturer, and you dare not turn up unprepared as you were expected to participate, so it is hard to deal with this sort of situation - But I want to do my best and make sure the students get the most out of it.

My fellow tutor on the course is an old hand a teaching fellow who takes the questions and essentially delivers a lecture, and I know this is not how it should be...


Thanks for any pointers!