when Valentines were handed out in elementary school by the "postman" - designated by the teacher. We each had a brown paper bag on our desk and as the postman came by and "delivered" a card from someone you knew or "guess who" - you put it in your bag. It was an anxious time as each of us worried secretly that our bag might be empty at the end. I suppose the brown bag was to prevent anyone from knowing how popular you were or unpopular if that was your fate.
Fortunately, by the time my children were in school the policy was more forgiving. You were required to give a Valentine to everyone or no one at all.
Not everything in the past was better.....