“Diary of a Wimpy Kid: Rodrick Rules” takes our intrepid wimpy hero through seventh grade — more struggles to be “popular,” more efforts to make his unaffected, unpretentious and childish pal Rowley less of an embarrassment. It makes more of an effort to connect the big screen “Kid” with the Jeff Kinney “Diary” books — lots more animation in the Kinney stick-figure style.

It just takes a very long time to get going.  Apparently seventh grade doesn’t pack as much potential for amusing, scarred-for-life  trauma as sixth grade.

The problems of Greg Heffley (Zachary Gordon) lie much closer to home, this time around. His baby brother Manny is old enough to talk and old enough to rat him out. And older brother Rodrick (Devon Bostick) has become “the king of laziness, except when it comes to torturing me.”

Thus Greg’s academic career is hampered by teachers who tar him with the same brush as his under-achieving sibling. Greg’s crush on the willowy new blond model-classmate, Holly Hills (Peyton List) is doomed by Rodrick’s pranks at the skating rink and at church.

Thankfully, Mom (Rachael Harris) has noticed the boys aren’t getting along. A delusional self-help newspaper columnist, she concocts a scheme to pay them to get along.

“Having a brother’s one of the most important relationships of your life,” she lectures.

Rodrick manipulates this do-goodiness into a way to pay for gas for his van while he continues to trick and torment Greg and steal mom’s eye-liner so he can look the part of a rock drummer in his band, Loded Diper.

The sibling rivalry doesn’t have much to offer until late in the film, when Rodrick starts passing on his “rules” for getting by to the wimpy kid — “Don’t be good at something you don’t want to do,” say washing Dad’s car. “Always lower Mom and Dad’s expectations.”

Another mom trick, forcing the boys to spend the weekend with their grandpa in a retirement home, leads to a funny chase-in-his-underwear memory for Greg.

But as in the first “Wimpy Kid,” school holds more promise for comedy as Greg creates a cruel “nobody sees you” game for his classmate Chirag (Karan Brar, hitting the affected Indian accent too hard). There are weak gags involving the gross classmate Fregley and the goofball Rowley (Robert Capron) inadvertently teaches Greg how to lip-sync to Kei$ha and to be himself, not try so hard to fit in.

As kids’ entertainment, “Rodrick Rules” is harmless enough.  But it’s less broad than the first film and less funny.  Animator turned director David Bowers has little to work with in this script and once again no money to spend on funnier actors in supporting roles.  Steve Zahn, playing the dad who is wise to the ways of sneaky throw-a-party-while-the-parents-are-away boys, manages a laugh here and there, as does Harris as the smothering-hovering mom. But no funny teachers, and most of the Westmore Middle School classmates seem to have aged out of their amusing years.

Without more giggles, this “Wimpy” sequel simply wimps out.

Rating: PG for some mild rude humor and mischief.

Cast: Zachary Gordon, Devon Bostick, Robert Capron, Rachel Harris, Steve Zahn

Director: David Bower, written by Gabe Sachs and Jeff Judah, based on the Jeff Kinney book. A Fox release.

Running time: 1:39

Running time: 1:38