With a 1st & 4th grader in our house we often take them out of school for a few days so that we can visit Disney when the crowds are low.
Epcot's World Showcase has a plethora of learning opportunities. What better place can you take your child where they can learn so much about different Countries hands on?! Encourage your Son to stop at the Kidcot Fun Stops around the World Showcase. These craft stops have Cast Members from that Country helping out & they are wonderfully open about teaching the kids how to say & write words in their language. My kids love asking them about customs in their Country.
Epcot's Living with the Land attraction has a tour called 'Behind the Seeds' where you explore the greenhouses and learn about agriculture. My kids LOVED this!
One of the Disney World Autograph books would make an ideal Travel Journal for your Student. Last year, my Son's Teacher requested that he write a journal & share it with the class instead of doing makeup work for school. He had a lot of fun with that!
Animal Kingdom definitely has learning opportunities around every corner! Cast Members are stationed around the park with cool facts like how much the animals eat in a day to showing how an animal's skull is shaped.
I've run out of room, but I hope you have fun!