It must be difficult to make a film about the ice age fun and lighthearted enough for children to enjoy, but the creators of the “Ice Age” films make it look easy. They’re currently on number four in the series, and have managed to get all the original actors back for the characters, including Ray Romano as Manny the wooly mammoth. And while it’s not getting great early reviews, the film’s target audience seems to be enjoying it.

It’s been said that the movie lends itself more to slapstick and the sort of physical comedy one normally finds in early-morning cartoons rather than on the big screen; however, because the “Ice Age” franchise has never been big on continuity where history is concerned, adding silly laughs doesn’t seem like much of a leap. The real question is whether or not the fourth installment will be able to change things up enough to keep audiences interested. Usually, the higher you go in the number of films, the harder it is to fill theater seats.

It’s a sure bet that the studio is counting on the antics of Scrat, the squirrel-rat who keeps viewers rooting for him through many failed attempts at claiming an elusive morsel of food, to keep kids wanting more. Joining Ray Romano for the cast is Denis Leary, Queen Latifah, and John Leguizamo.