Lindy,
Thanks for asking your question to planDisney!
No, unfortunately you cannot have the Park Hopper option added to only one day of a multi-day Walt Disney World theme park ticket. The Park Hopper option is designed to be added for the entire ticket duration and cannot be added only partially.
I know that is not the answer you were hoping for but think of it as a convenience that you use as needed. You never know if on one of those other days you might choose to hop after all, and you would have that choice available to you. My family has had more than once where we had no expectation to park hop, and then allowed a bit of spontaneity to rule the day and we hopped to another adventure.
BONUS TIP #1While there is enough to do in any given park to fill more than a day, we love to park hop at night to
EPCOT for some international dining. Rather than sit at a table service restaurant, we love to stroll around the World Showcase as a family, explore the stores in the different national pavilions, and share small plate items from the counter service restaurants and food stands. There are so many great choices, and it has been a good way to introduce my girls to new flavors and cuisines.
BONUS TIP #2
The addition of the
Disney Skyliner has made park hopping between EPCOT and
Disney's Hollywood Studios very convenient. Also remember the ease of moving between EPCOT and the
Magic Kingdom Park via the
monorail!
Write me back if you want some great hopping suggestions.
Have a Magical Vacation!Doug