As trainers, we love the group discussion. Often, we break our class up into smaller groups for peer discussion. Then, we ask each group to report back to the group with their top three. Either you need a scribe for the peer groups and/or a scribe to collect the responses from each group. If everyone had access to ONE flip chart that would stick around, discussions could reflect back to the notes as the training progresses. Or, perhaps there was a way to ensure all learners get a chance to participate and have their voice heard by posting their thoughts or questions.
In the past, I've highlighted PollEverywhere.com as an option. It is a nice "clicker" or audience response option. But I'm talking about a continuous flow of thought. Consider using TodaysMeet.com.
Without logging in, you can create a meeting room where the users can meet up and share their thoughts. Users don't need to log in either. The room is open to anyone with the URL, but you get to create your own meeting room and name. Also, choose for how long it will remain open (choose anywhere from two hours to one month).
Open the meeting space up in the front of the room. At various times in training, ask for the group's feedback around a particular topic or question. It can be used for individuals to participate or groups following peer discussion. By leaving the discussion open after the training session, you or the learners can return to the room and add follow-up thoughts or response to questions after training.
For more control, like pausing the conversation or keeping the conversation indefinitely, you can sign up for free for the Teacher Tools.