24-Hour Layover at CDG: What Would You Do?

Greetings,
We will arrive at CDG before 9AM on a Tuesday morning in early September. We have a flight to Florence the next day, and I’ve secured a hotel room at the airport for the night. We should have time to drop our luggage and make a day of it, but where to go? Obviously, we can make our way into the city, but since we are already so far out, is there somewhere we might visit that isn’t Paris? We will spend a week later in our trip in the 7th, so we will have plenty of opportunities to enjoy Paris. Thanks for any and all suggestions!