My best was LONG before highschool. As an elementary school kid, I just happened to find a bunch of rusted old nails on the ground. It must have been 3rd or 4th grade... I have no clue what possesed me to try this, but I went around selling them as much as $0.25 each. Kids would buy them! I have no idea why, but I made some good candy-money like that. Nowadays I have set off the Aviator Sunglasses fad again. It started with a school play where I always wore them before rehearsal. After a few days a couple of people wanted them. I went and bought them at the local BX for $23, and sold them for an even $25. All the Nazis (It was The Sound of Music) wore them for the curtain call on the last night, and it became legendary. I bumped the price up to an even $30, and I just sold my 15th pair today. Gotta pay for Summer Seminar at the Naval Academy somehow, right?