A lot of parents skip or breeze through the World Showcase at Walt Disney World's Epcot. Why? Because they just don't feel like there's enough for kids to do to keep them interested. Used to, this was true. But in the passing years Disney took note and added some adventures for little ones so both they and their parents could enjoy this fabulous park.
Of course, Epcot is a park designed for learning. Disney created Kidcot fun stops in each country where your kiddos can create masks, talk to people who are actually from that country, and even get them to teach them new words in the country they're visiting's native language.
A great, cheap souvenir is a passport you can pick up for your child in Future World or around the World Showcase pavilion. The passport is just like a real passport--your child carries it with them to all of the countries and has it "stamped." If you are interested, you'll want to buy your passport before you start your journey. If not, you'll have to do some backtracking to get it full, which is not fun around World Showcase. Such a long walk!
If your child is someone who likes to have something no one else has, you can always make your own passport at home. Or if you'd like to have something personalized, you can check out a cool shop I found on Etsy that makes personalized Epcot passports. They also make autograph books in lots of Disney themes.
I guarantee you your child is going to learn a lot just from talking to the CMs in the different countries! If you are traveling while they are in school, you might even be able to work something out with the teacher where what they learn can be presented in class as a "homework assignment," alleviating some of what they will have to make up when they return!