Hello, Jane!
What a wonderful idea! Getting your grandkids Disney Dollars is a great way for them to think of
you as they get a souvenir from Walt Disney World!
In order to purchase Disney Dollars, take a look at
this link on Disney World's website. You can order Disney Dollars and pay for them via credit card, or you can pay by cashier's check or money order. At the time of this writing, a $15 shipping charge applies, and you'll need 2 weeks for processing (so you'll have plenty of time to get them for their upcoming trip!)
If you can't order Disney Dollars, check out
Disney Gift Cards, which we've picked up at our local grocery stores or pharmacies. These cards can also be used just like cash at Disney theme parks and resorts. (We've been giving these for family members who are heading to WDW in the near future, since they are so easy to pick up!)
No matter what, your grandkids will be so happy that you are thinking of them when they are in WDW (and, then, they'll be thinking of YOU!) by providing them with the means to bring a bit of the magic home with them. You'll all enjoy the story, too, of how they decided on just the right item, when they return and show you their souvenirs!
Please send any additional questions you may have as your grandchildren head to Walt Disney World! I'd love to help!