Emma, we started very slowly. My students sit in teams of 4 from the beginning of the year and I refer to them all the time as a team. I narrate on a regular basis the importance of relying on each other and asking each other questions. Next week, I will start slowly by establishing a protocol of a homework goal for the team. They will get a bonus point if everyone in their team does homework. every week, I will add to the team check idea. One week it will be teams I notice helping each other, they'll get a point. I will build on this with noticing keeping each other focused during group work, get a point. At the end of a two week period, the team with the highest points will get a prize (pencil, stickers, something like that). I just keep building and messaging the importance of working in a team.