I'll tell students that, if they have a question about what I'm saying, they can post it to Twitter with the hashtag #biol234. When it's time to pause for questions, I'll display the #biol234 Twitter feed on the screen for everyone to see. Maybe I'll give us all a minute to read the top questions, and then I'll answer them, integrating answers to different questions where this makes sense. And then I'll ask for verbal questions.
Students in the class can follow the #biol234 feed on their smartphones and laptops, and can 'retweet' questions that they think important. Questions that are retweeted will rise to the top of the feed list. The lecture room has two screens, so I plan to use one for the powerpoint slides from my laptop and a second for internet content from the built-in podium computer. (This screen will be blanked when I'm don't want students to attend to it.) One web tab will be the Twitter feed, ideally set so only the top 5 or so questions are visible.
Other features and concerns?
Students can also use Twitter to answer simple questions posed by other students.
Students who want to contribute will need to have Twitter accounts as well as smartphones or laptops. This is good - I don't want questions to be posted anonymously, as this can lead to silliness and unpleasantness.
Students won't be disadvantaged by not participating. If they don't bring laptops or smartphones to class, or just don't want to use them for this, they'll still see the Twitter feed and and my responses.
Won't students who follow the #biol234 feed on their smartphones/laptops be distracted? Well, they'll be distracted from watching me, but at least they'll be thinking about the material.
One thing I really like about this is that it will help shift the focus from answers to questions.
If this works well I'll need to shorten the presentation parts of my classes, to allow more time for the questions, but this is something I'd want to do anyway.
I don't know anything about Twitter apps, but I suspect that the Twitter web site isn't the best interface for what I want to do. I'll probably ask the students for suggestions, but I'd appreciate any suggestions from readers.