Dennis Quaid Takes Young Girlfriend on Boat Date on Lake Como

Dennis Quaid is taking advantage of the last week before school is back in session ... bringing his smoking hot, grad student girlfriend on a romantic getaway in Lake Como!!!

As we all know ... age ain't nothin' but a number -- but you can tell 65-year-old Dennis is having a grand time with 26-year-old Laura Savoie. Easy to see why in these killer vacay pics.

Seems Dennis has a thing for millennials ... he split with 32-year-old model Santa Auzina earlier this year, and now his new GF is even younger!!!

Dennis and his sexy co-ed still have a lot in common despite the huge age gap. He's from Texas, she goes to the University of Texas, and they both love speedboats!!! Match made in heaven.

Laura doesn't have to go back to class until next week, so Dennis has plenty of time to end their summer with a bang.