Tools/backchan.nl/description
The back-channel is a term to describe what the class might be saying or thinking during a lesson. “backchan.nl” offers a way let the audience of presentations(ta) comment or ask questions(ta)/polls(tool). They could also be voting(tool) on the importance each other's questions - which is a great opportunity if you've ever wished a question and answer session to end. The voting then allows the presenter to prioritise questions that merit answering. As well as know what is going on in the 'back channel', this tool is claimed to make better use of that Q & A time. You might use it while showing a video, or dare to use it while talking at length to the class. But here you also have a means to encourage pupils to actually ask questions, and furthermore, have them think about each other's questions.