You are taking the right attitude towards this class. You are right not to focus too much on accuracy and to encourage contribution. Well done!
Unfortunately for you, you’re dealing with an age group that is reluctant to speak out in front of their peers and especially reluctant to express an opinion that is different to the rest of the class. This means that if you are doing work that involves expressing an opinion, if it difficult to get the first person to state their opinion. You haven’t said what type of speaking activity you’ve done with the class but my advice to you is to stay away from anything that involves expressing an opinion (debates, etc).
You could try any or all of these:
dialogues where they substitute some of the words themselves
students prepare questions for an interview
find someone who... exercises
dictations in pairs (in pairs students read texts to a partner; the partner writes it down)
picture dictation (one student has a picture, he/she describes it. The partner draws it) .
The ideas above will get students speaking in a controlled way. When they are more confident and used to speaking , you can introduce different activities.
Also take a look at these posts where I’ve answered similar questions.viewtopic.php?f=2&t=602viewtopic.php?f=2&t=3150
All the best,