We used to do a weekly quiz. It was quite popular actually (which surprised me).
We used google forms for ours because that way only a staff member running the quiz could see the responses. We used forms instead of the polls available on Discourse because it looked better and was quicker to make. This was also before the time that polls got a bit of a revamp such as having the export button. I think nowadays we would be inclined to use the polling feature.