divorcing family

So my boyfriend and I have been dating for 2.5 years and I get along with his family pretty well. But now his parents are planning on a divorce and it's impacting him heavily. I know this is a hard thing for him but things besides his mood has been changing. Like he was always a good student but now he's ditching and I think he's reacting worse than he thinks he is to the divorce. I've never had divorced parents so I don't know how to help or what to say. I don't want him throwing his life away but I want to help. Can anyone give me some advice??