My kids loved meeting others at the teen club, so I’d suggest going the first night. My kids were 14, 14, 16, 19 and 20 on our last cruise, the teens all met a group of kids their age, but we also spent a lot of time as a family going to shows, karaoke, hanging in lounges - I don’t recall anything the younger kids couldn’t do with us (except spa, we didn’t get passes for the over 18’s, just for us)