Tisdale’s Bethany Pearson appears to be present in Aliens in the Attic, as a narratively defensible character, merely so that her boyfriend, Ricky (Robert Hoffman), who turns out to be older than he has lied about being, is in turn present to set up some technobabble about the aliens only being able to target adults with their mind-control doohickey. Aliens? Oh, yeah: The Pearson clan has headed to Michigan to what could only be termed a summer mansion, all set for some R&R, only to discover their vay-cay thwarted by a gaggle of green, spudlike critters from outer space who are somewhere at the intersection of post-midnight-snack Gremlins and E.T. gone psychotic.

It’s funny, see? They’re aliens, and they’re small, and they’re mean. I don’t think it’s funny, of course, because I left grade school many years ago, though I was able to manage to divert myself by trying to guess who was voicing the CGI aliens. (I only guessed Thomas Haden Church: Imagine That, Spider-Man 3.)

The Pearson kids include Tisdale’s Bethany and her math-nerd teenage brother (Carter Jenkins) and cutesy-poo little sister (Ashley Boettcher) plus their three male cousins: one wiseass teen (Austin Butler) and two videogame-mad prepubescent twins (Henri and Regan Young). There’s a lot of rancor among them that is instantly thrown into the lake as soon as the monsters arrive. Because, you know, exploring the dynamics of extended families is not on the agenda here. Bashing grotesque little alien invaders over the head is. And only the kids know what’s up, naturally -- children being the wisest and most capable among us, or at least it looks that way if you’re nine-years-old sitting in the multiplex with your pervy dad in the summer of 2009 -- and only the kids are left to save the planet. Because their parents (Kevin Nealon [Get Smart, You Don’t Mess With the Zohan], Gillian Vigman [The Hangover], and Andy Richter [Madagascar: Escape 2 Africa, Semi-Pro), while clearly not stupid, are just as obviously deaf: My parents could hear me and my brothers merely plotting mayhem all the way upstairs in our bedrooms, but these can’t hear an actual battle raging? Sheesh.

I suspect the two videogame-crazy twins wrote this flick, because it plays like something off a console: Watch out for the antigrav grenade on Level Two! Don’t forget to pick up Nana’s alien-mind-control remote on Level Five! Actually, Mark Burton and Adam F. Goldberg wrote this flick, and I would have expected more from them -- considering that they’re responsible for, respectively, Wallace & Gromit: The Curse of the Were-Rabbit and Fanboys -- than a gang of smug, annoying, obnoxious brats the likes of whom make one glad one never had children. I mean, if a movie could be an effective birth-control device, it would be this one. I don’t care if the rugrats here saved the planet -- maybe it’s not worth saving if this is who is going to inherit it.

Five minutes into the film, I already was hating these monsters. The kids, I mean, not the aliens (though the aliens were boring and unpleasant too). I was hoping the kids’d get face-hugged and embryo-implanted by acid-drooling aliens. No such luck. It’s all just sci-fi slapstick, jokes about rotary phones, and getting grandma (Doris Roberts: Dickie Roberts: Former Child Star, All Over the Guy) to beat up on Ricky Matrix-style.

But we probably shouldn’t find that surprising at all, considering that director John Schultz inflicted the awful 2005 Honeymooners movie on us. This movie, like that one, isn’t so much a movie but a shadow of a reflection of what a movie should be, a lazy, half-assed collection of random ideas about what makes up a halfway decent movie.