Sad thing is those people won't collect many house points despite being active players, mainly because they dislike doing homework. The reasons for that differ. Some lack the time, others dislike the idea of writing monologues.
Some of you might say there will be less people doing homework if the opportunity to gain points by roleplaying is given. In my opinion this would rather encourage more players to roleplay and do homework at the same time than discourage them from the homework.
A valid point to consider is the amount a player gets for the plays. I'm not a specialist in programming but I hope it is possible to add a letter/word counter which has an underlaying algorithm transforming the written letters/words into house points.
My guess is this would make a lot of users really happy. It's just a rough idea that definitely needs to be accomodated but I hope you give it a chance. :)
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