My players keep getting distracted

My players keep getting distracted during each other's turns in combat when I'm describing things they think don't apply to them, pretty much all the time. I have tried various things, with iffy success rates. By the way, these are players aged 10-18(a couple of campaigns). They go on their phones, spin their dice like a top, and-especially the younger ones- they talk over me and others. This is more of a problem when I have a bigger group, since I play in a local restaurant that hosts a game night on Fridays. Also, how should I catch up players if they miss one or more sessions?