Should I write him a note?

So there's a guy that comes to the Wednesday night teen bible study at my church and I work with little kids so we aren't in the same class. He used to come (early 2015) and always be smiling and wear his cowboy hat and boots😍 and then he got in some trouble and went a way for a while if you know what I mean and then he came back twice in October and I didn't get to talk to him and he was there last  week and he never smiles anymore and just seems down. but I was busy with the little kids so There's not much time in the night to talk to him so a friend suggested I write a note and ask the teen leader to give it to him (it would be anonymous). Just something short to let him know someone cares about him and give him a compliment. I'm 15 (almost 16) and he is too.Sorry that's kinda long, good job if you read it all