"Drawing Preschool"
Using Drawpile (https://drawpile.net/), A big ass canvas can be used to allow people to draw whatever they like within a certain time frame. Updates would be posted on the thread.

If you have any ideas on what to add, feel free to say ( ´ω`) — I might change the "draw whatever they like" to something more specific, since that would encourage more creativity, but I would like to see first if that sounds like a good idea or not ┐(ﾟ～ﾟ)┌