Hi Sara!
Thanks for visiting the Disney Parks Moms Panel with your question!
My kids both enjoy Pin Trading at Walt Disney World and have done so now for many years.
Starter sets are sold at the parks, in the Disney Resort Hotel gift shops, or even online on the Disney Store website. If your child has a particular character or 'theme' in mind, this can be a great way to start out.
Pin Trading Starter Sets can be anywhere from $17 - $25 or even more, depending what type of set you'd like and how many pins are in it to start. I've included a link to a starter set on the Disney Store online site which includes 4 pins (2 duplicates meant for trading away) and a lanyard.
Alternatively, consider purchasing a grab bag online and let your child select their own lanyard upon arrival at Walt Disney World. A great place to purchase a 'lot' of pins is on a site like eBay. I've often purchased this way for my kids since the purpose is to get a bunch of pins you'll be willing to trade
away - in favour of the pins you want to collect. Be sure to read the auctions carefully to ensure that the pins you're purchasing to trade away are all genuine and from a highly rated seller. You can often purchase a 'lot' of 25 pins for around $15-20 which is a great way to get started.
Your kids can approach Cast Members they see with a lanyard or pin 'pouch' on and ask to trade. Pins are traded one for one and the child gets to make the decision on which if his or her pins to give away to the Cast Member in the trade.
If you have additional questions about pin trading, please feel free to write me back Sara. I'd love to hear from you again.
Wishing you a simply Magical time at Walt Disney World!
Kirsten