If a child wants to buy a pack of valentines these days, their choices are limited and mostly uninspiring. They are nearly all designed around famous TV or movie characters (Harry Potter, Tinkerbell, etc) and usually follow the same format: rectangular, small, featuring a colorful scene of the character and some catchphrase. They seem less about expressing one's feelings and more about free advertising for Disney.
I was recently cleaning out some old boxes from childhood, and found these vintage valentines that date back at least to the 1970s. I was amazed at not only the range of characters, but the clever little concept behind each one, right down to the apple you cut out and put into the basket. I also scanned the back of some, which are great little one-color adaptations of the front.
Of course, as kids we also made our own valentines with construction paper and sparkles. But these were certainly inspiring for creative young minds – they sure don't make them liked they used to!