I won't say it's an excellent idea but it's interesting. I probably wouldn't do it but if you do go through with it, go prepared and keep a positive mental attitude the whole time. And if you do go though with it, we want the skinny afterwards. Ribbit
I say take a shot and do it. you dont read as the type of person who would walk up to a dealer and say, " Gimme a better coin than the one I got.". Good luck.
Things like this are always worth a try. The primary difference here is if you read most success stories like the one about trading up from a paper clip, you'll notice he probably spent thousands of dollars traveling, posting, writting, calling, etc. to accomplish this. Others, as noted, may go from door to door and if explained as a charity, school experiment, etc., may work due to the time and just wanted to thow it out anyway. Remember at a coin show every dealer is there to make money. They spend thier own money renting a space, table, gas and oil in thier cars to get there, food and drimks while there. Then most of their profits are used to support a family. So just why would they just trade upward for you? It could happen though so why not try. At many coin shows I've seen dealers just give a kid a coin. Although that is usually so the parent may feel guilty and purchase something. Of course there are those dealers that just are nice people so try it.
Can never edit my posts for some reason. Just thought I say one more thing. There is a church in my area that asks everyone for anything as a donation. Not money, just stuff for a sale. Then once a year they havea a FREE flea market and give away all that stuff. It has been a massive success every year. People all over the area give them items. And that FREE flea market they have is really fun just to watch. Amazing how many people will give something away knowing it will also be given away.