Q&A for engagement
Questioning students is one of the staple techniques employed by teachers. However, the virtual environment has emphasised the issues with some approaches to Q&A in the classroom. Some students appear to disappear during Q&A segments of lessons; others have technical issues (real or idealised!); while many teachers have badly-damaged tongues from the amount of biting they have had to do during awkward silences.
The good news is, effective strategies for engagement during Q&A in a physical setting also work in the virtual environment! Here are some suggested approaches.

Cold calling

Cold calling was made famous by Doug Lemov in his book Teach Like a Champion. The UK's Chartered College of Teaching provides a useful one-page summary of the technique. Cold calling works well in a virtual environment because:
  • More rapid fire Q&A tends to stutter a little when students at home take time to unmute themselves or have technical problems.
  • The random nature of the Q&A keeps everyone on their toes, increasing engagement.
Cold calling: asking a question, pausing to let everyone think of the answer; selecting someone at random. No hands up!
I have also been using a great free tool to jazz up cold calling and make the process visible to all students:
Random Name Picker

Hinge questions

This approach goes by some different names, but the concept is simple. At some point in a lesson you may need to check your students' understanding, but asking one student for an answer doesn't tell you if everyone does indeed understand and allows most in the class to disengage. So, instead everyone writes an answer and everyone is engaged. A common approach to this in normal times would be mini whiteboards, but in a virtual environment this isn't effective, if possible.
Source: Morter, Emily. Unsplash, 2017.
Instead, there are some simple tools you can use to gather responses. The simplest might be the chat function of your video tool, but I have noticed the enthusiastic students always answer first and then the rest type in an answer a little bit like 'What she said above...'. So, I've used two methods which, even if you don't use Google Apps for Education, can be replicated in other ways.
Google Forms 1-3 questions, open-ended or multiple choice. Link shared with students. Check learning by reviewing responses (this can be done live with the class, if you feel they are comfortable to have any mistakes highlighted). Similar tools: Microsoft Forms for Education, freeonlinesurveys.com
Peardeck This awesome add on for Google Slides allows you to build interactive question slides that all students can write on. Then you can share the class answers to check understanding and generate discussion. It is also anonymous. Similar tools: Mentimeter, Peardeck for Microsoft (free trial).

Gamified Q&A

Who doesn't like Kahoot?!?! This has been a staple part of many teachers' toolkits for years, and it works wonders in the virtual environment. While many quizzes created are 10+ questions long, and therefore take some time, I've found Kahoot increasingly useful as a means of quickly engaging students and checking their understanding mid-way through a lesson. I create 2-3 questions per check and may have 2-3 checks per lesson. It is seriously easy, and the free version is good enough most of the time.
Get your students in the habit of having Kahoot loaded up on their device so that they can quickly log on to the quiz.
Download the results sheet and use it to track progress.
Kahoot works amazingly well with cumulative quizzing (below).

Cumulative quizzing

Nothing demotivates a student like feeling they aren't making progress. This isn't a specific suggestion for virtual learning, but general advice as to how you can build student engagement over time through motivating them. If you spend some time creating a quiz for your students, why just use it once? Wait a week or two and then use the same quiz (or a very similar one, where most questions are the same as before) to test their knowledge. Students should increase the number of correct answers they achieve, then they will feel a sense of success and progress, and, hey presto, you have more engaged students.