I have 10 year old twins (Year 5). One recently found out from friends that Santa isn't real. He is ready to stop believing and is not particularly affected by knowing the truth. He declared at the dinner table that he knows it's not us and my other boy heard the whole story. My other boy is still in the magical childhood phase.
They don’t have any siblings so I can't say that we have to keep the magic alive for a younger sibling.
How do I do the presents? No more writing their letters. They usually have a stocking and a couple of presents from Santa, then a couple from us and a couple from grandparents.