Is writing letters relevant this days?

First, with regards to all the environmental people, they think snail mail is a waste of trees. Second, with the internet and technology, snail mail seems almost ridiculous except for the fact that people who can't afford internet and other digital services would have no way of communication so it is relevant and must continue. For legal purposes, as in proving a document was delivered, snail mail is most necessary. Try walking into court with no proof a document was sent. The signature will usually seal the deal. In answer to your question, yes snail mail is relevant and needed still today. As for pen pals, I remember when we did that in school too. I think it's a nice idea but can be done electronically just as easy.