When I was in Korea back in '88-'89 we'd get batches of pen pal letters and cards from school kids, usually around Christmas or a holiday. It was most likely just random that he got this particular batch of letters. Sometimes when you're 8,000 miles from home even a letter from a stranger is better than nothing at all. In this case it's not.
Makes you wonder what our servicemen might want to focus their energy on when they get back home. I think they need to look squarely at what the 'greatest generation' has let slide (my parents included, sadly). I think I'd want to visit that school, in uniform.