As you know from seeing our past collections of bizarre discussion placards from the '70s, we love vintage school posters -- and we found a treasure trove of them on Etsy.com, including erotic plants, smiling tighty-whities and more.

Count down our top fifteen below, and click on the links if you'd like to make one of these oddities part of your personal collection.

Number 15: Talk about a come-hither look.... Number 14: "Let's check the Bible to make sure God made these." Number 13: Doesn't the underwear look a little too pleased with himself? Continue to see more of our top fifteen vintage (and strange) school posters. Number 12: "Look, Ma -- snacks!" Number 11: Who knew mushroom fungus could be so arousing? Number 10: "Mom, you know you're giving me cat food, don't you?" Continue to see more of our top fifteen vintage (and strange) school posters. Number 9: Looks like she just got a "Dear Dick" letter. Number 8: And you thought mushroom fungus was arousing.... Number 7: This is Peter's what? Continue to see more of our top fifteen vintage (and strange) school posters. Number 6: "What's your interest in family jewels, Grandpa?" Number 5: Cheap at twice the price. Number 4: Do you only have to honor them if they have halos? Continue to see more of our top fifteen vintage (and strange) school posters. Number 3: Hope all those rabbits done give Johnny and Susie any ideas.... Number 2: "But when I grow up, I want to be a designer of really high-waisted pants." Number 1: "But it smells so good!"

More from our Lists & Weirdness archive: "Bizarre classroom posters from the '70s, Part 3: Behold the roots of memes."

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