Students are not here to pour information into. I wanted to engage student and I found the best way was to ask. As relationships were forged students became more comfortable with asking questions.
Ask them and they will tell you know what they want to know.
Engagement for some might be found in a book but I want to see science in their world not just in the world of textbooks and science class.
It is hard for a science teacher to answer some questions and I did not what to trivialise the science when answering student questions. In some circumstances using some newly acquired concept enabled students to answer their own questions.