Jimmy Fallon's new children's book 5 More Sleeps 'til Christmas is available for purchase now at FAO Schwarz
Jimmy Fallon FAO Schwarz
Jimmy Fallon
| Credit: FAO Schwarz

It may not quite be Halloween yet, but Jimmy Fallon and his family are already getting into the Christmas spirit!

The Tonight Show host opens up to PEOPLE in an exclusive conversation surrounding his new children's book 5 More Sleeps 'til Christmas about his family's holiday plans, revealing that first and foremost, he and wife Nancy Juvonen teach their daughters Frances Cole, 5½, and Winnie Rose, 7, the importance of giving back.

"At first, they were a little upset. They're like, 'No, we want to keep everything.' I'm like, 'You can't. ... Trust me, if you give, you receive — you get back more than you can know.' So that's what we kind of taught them. And so every [Christmas and] birthday, we do that," says Fallon, 46. "They pick some toys and we give them to a center by our house that takes in toys."

Despite the lesson in generosity, the father of two admits his girls are "still spoiled" anyway. "They have too much," he tells PEOPLE. "They definitely have more than I had when I was a kid."

As for how their holiday plans have been affected this year given the ongoing COVID-19 pandemic, "Usually we'd have the whole family over and I think this year's different," says Fallon. "We'll be talking to everybody and FaceTiming and whatever we can do. I don't think my dad understands Zoom yet, so just FaceTime was a big leap for us. But yeah, it'll be different and tougher, but we got to do what we can to get through this."

Winnie and Franny will also make sure they get in contact with Santa Claus (who usually "writes a letter back," their dad says), and the family will "leave out cookies and milk." too. Adds Fallon, "I think we leave out a carrot for the reindeer, which the reindeer doesn't finish, so far. They leave a couple of chunks still. Rudolph does not finish all of the carrot. Very interesting."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

Jimmy Fallon and family
Jimmy Fallon FAO Schwarz
Jimmy Fallon
| Credit: FAO Schwarz

Illustrated by Rich Deas, Fallon's newest addition to his children's book repertoire — which debuted at No. 1 on Amazon's best sellers list — was inspired by his "favorite time of the year," as well as a conversation he had with Winnie while walking her home from school when she was around 5 years old.

"She said, 'How many more sleeps 'til we go to Grandma's?' And I was like, 'How many more sleeps? That's so cute.' I'm like, 'Oh my God, I've never heard that before,' " he tells PEOPLE.

"I go, 'That's a good idea. Maybe that's something like, how many more sleeps 'til Christmas?' So I said, '5 More Sleeps 'til Christmas, and you can describe those five days leading up to the biggest day of the year when you're a kid,' " recalls the Saturday Night Live alum.

Fallon adds that the book is also based on "all the traditions you do and the decorating and hot cocoa and the candy canes. So I wanted to do something with that. Then we found an illustrator that just set the right tone. And I'm like, 'This kid with a big head, just dreaming, looking out the window.' "

Jimmy Fallon FAO Schwarz
Book cover for 5 More Sleeps 'til Christmas
| Credit: FAO Schwarz

RELATED VIDEO: All the Details on Lifetime's 30 Christmas Movies: Get the First Look Now!

Fallon teamed up with FAO Schwarz in celebration of his new book, and for a great cause. For every copy sold, the company will donate a toy to St. Jude's Children's Research Hospital.

In fact, FAO Schwarz's flagship store within New York City's Rockefeller Plaza has set up an entire "wonderland" section dedicated to the late-night host's new story.

Also behind the whimsical window display are his "top toy picks for the holiday season," including their dance-on piano mat (made famous by Tom Hanks in 1988's Big), cars, trains, plush toy soldiers, dolls, LED easels and more.

"[Even] if you don't buy anything, the experience of walking around that many toys and that much magic is so cool," Fallon says. "It just makes you feel like a kid again."

5 More Sleeps 'til Christmas is available for purchase now at the FAO Schwarz store and FAO.com.