No lesson plan here yet.... But I made a few useful things.
First is a list of boys/girls names from the Harry Potter series, in alphabetical order. I didn't include ALL the names, but there are 34 names for each boys/girls.
I figure I'll try to convince my students to adopt a Harry Potter name for the duration of the camp.
Next is a simple name tag template. 4/page. Included are the 4 house badges, in squares that are the same size as the name tags. I'm going to hand them out at the sorting and have the students glue them to the back of their name tag.
Finally (my favourite) is a simple house points chart. I really liked the ppt version available in this thread, but i wanted something to post so it's visible the entire time. I'll either buy coloured stickers to place up the chart or just colour it up with markers. I haven't decided yet.
Hope something can be useful for you. I'm super excited for my Harry Potter camp

Thanks for all the amazing ideas in this thread, I've picked through most of the stuff and will be using a variety of different ideas from everyone. (I'm teaching middle school) If I come up with something new I'll post it later.