This idea is ripped off a system we have in the U.K. (and ofc Harry Potter) where students are sorted into 4 houses/teams and are given points for homework, volunteering, interacting in class etc. Its not really possible to convince every teacher in the school to play along, so I figured it would be better to give them stickers instead of points and give the students individual awards if they manage to collect 20 stickers.
I'm giving the students stickers for homework (sometimes optional), participating in class, winning activities and interacting with me and the English teachers (In English) outside of class. My JTEs have created a sheet in which we sign if a student speaks English with us so maybe talk with your JTEs to see if this is something that they'd be willing to do.
Of course, you can easily adapt it so that you get the whole school involved (see below). Although I would love to do it, I don't have time this year so I am just doing it for fun. The power point I've attached below includes an explanation and a spinning wheel which assigns the students a house.
How to adapt it to get the school involved:
Split the students into even amounts so that each team has a fair amount of students (If you have 4 classes in each year, you could just assign a team to each class).
Keep a tally on your English board so that students can see which team is winning (You'd have to make sure to keep an account of how many stickers each student has).
At the end of the semester, award the winning team with something (also award the highest achieving students)
Drive link: https://drive.google.com/drive/folders/1CtOtCa3V6JpwKE0d2SHKaRQppWJBFK1V?usp=sharing