My suggestion is to implicate the students more in their learning process by getting them to choose what they talk about. Give them homework to prepare for the next class for example:

Role-plays: the students write spicy role-plays for other students to act out. So you have a cast of characters, each one with an agenda to put forward and argue for at an upcoming meeting. Students create these using their imagination and inventiveness. In the next class let groups act these out. The students are likely to be interested to see how their particular role-play goes when acted out by others.

Debates: Students pick the topic themselves and pair up with a debating partner who has selected teh same topic. Both parties prepare in advance of the debate.
The class will vote after a ten-minute period only. The two speakers must speak for equal time. The teacher times this. Questions may be taken from class during the debate. The president times the speakers and takes the questions. The speakers are aiming to win as many voters to their cause.

It is important that the students pick their own topics and they don't have to be serious. If someone wants to debate that dogs are better pets than cats then let them!

Quizzes - have the students write quizzes for their fellows. Make several teams and have a play off. Quizzes can be grammatical or general knowledge. If students make grammatical quizzes they do so with the help of a grammar reference book and try to find grammatical points that are difficult to catch the other team out.

Students will be interested to see how other teams do answering their quizz. The idea is to come up with the hardest quizz.

Well try these ideas - the ball is really put in the students' court and with that responsibility for their own learning they are likely to become more implicated in the lessons.

Do let me know how it goes!

For more ideas and some sample games try this web page:
www.teachingenglishgames.com/adults.htm

Shelley