Patrick Renna is making sure his sons are just as big of a baseball fan as he is.

The actor, 45, who played Ham in the iconic movie The Sandlot, spoke with PEOPLE about his new children’s book A Little Slugger’s Guide to the Unwritten Rules of Baseball and Life and shared that his own kids, sons Flynn and Liam, are already getting into the sport.

“It’s funny, Alex Rodriguez said something cool, which was that the most important time in a kid’s sports journey when they’re young is actually not on the field,” he tells PEOPLE. “It’s in the car ride home.”

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“And it’s getting them to still be interested in it, because my oldest, Flynn, the first two, three years of baseball [he] didn’t want to do it,” Renna continues. “Now he finally has this amazing team and he loves it, and he just wants to practice three times a week, and he got so much better and it finally clicked.”

The dad of two explains that while it was tough for him to see his son not enjoy the sport he loves so much, the car ride became really crucial for his family.

“And in that car ride home, it can’t be about, ‘Did you have fun?’ You can’t play those games either,” Renna says. “So I think just watching them sort of excel in sports, I tell them both — and they’re both pretty young still — but I say it over and over, you just have to play.”

As for whether his kids have attended a professional baseball or basketball game yet, Renna says he’s hoping he’ll be able to take them soon.

“I got to figure out how to do it because going to baseball games is a little…it’s tough sometimes,” he admits. “So I got to get the Dodgers to give me some box seats or something so I can take my kid there. But he went with his team and his mom took him and he loved it so much.”