Those booking They Might Be Giants right now can choose from a menu of three different packages: There's the basic anything-goes set, the 20th anniversary of "Flood" celebration show and then the one that helps you learn your numbers and ABCs.

That's the one that's sold out the New Hazlett Theater for two shows on Saturday.

It shouldn't come as any surprise that the quirky little New Wave band fronted by the two Johns - Linnell and Flansburgh - would be a hit among the elementary school crowd, considering that parents have been turning their kids on to songs such as "Particle Man" and "Birdhouse in Your Soul" for generations.

In fact, scan the titles of They Might Be Giants' four "family" records - "Robot Parade," "Where Do They Make Balloons?" "Who Put the Alphabet in Alphabetical Order?" - and they don't look that much different than the band's proper catalog.

Parents taking their little ones to the show might be pleased to know that it's not drastically different from the band's typical appearance.

"We use the exact same set-up for both shows, we just turn the volume down a little bit for the kids," Mr. Linnell says. "We're wearing the same clothes and the show looks like the same, and a lot of the material overlaps - maybe a third of the material is the same in both shows. It's just a matter of the response we get from the audience. It's a completely different type of audience and that affects how we perform in a way.

"There's something a little challenging in performing for kids in that they're not as accustomed to the formal rites of the rock show. They don't know the drill as fully as grown-ups do. That feels very different, you know. With kids you're having to be more explicit and use simpler words and not make assumptions about what they already know, and that carries over into the performance. We also don't worry too much about what's going over the kids' heads. Kids are not bothered by not getting every single thing - I think they're used to that idea."

They Might Be Giants' lucrative side career as a kiddie attraction started in 2002, 20 years after the Brooklyn duo formed and eight albums into its career. It wasn't the fulfillment of any master plan for the band.

"We got an offer from Rounder to put together a kids record," the singer-accordionist says. "We were not thinking hard about the consequences. We were just thinking this was pure fun for us and there was every possibility that this would not be a major deal for anybody. We were taken by surprise when the CD outsold the previous They Might Be Giants album by a wide margin. It was kind of exciting and delightful that we could do something that was pure fun and very low stakes and have such a great response. We were not feeling very pressured about it at any point. I think that's why it came out the way it did. It didn't sound like we were selling. It just sounded like us enjoying ourselves."

"Here Come the ABCs" became one of the band's best-selling albums and the logical sequel, 2008's "Here Come the 123s," won the band its second Grammy (the first was for the "Malcolm in the Middle" theme song "Boss of Me").

"We never won Grammys for doing the thing we set out doing," Mr. Linnell says. "But in a way that's fine because the function of the Grammy is more an item on the resume than anything else. It's nice for our moms and dads, but I don't think our friends give a crap about awards. And I would guess that's probably true of the core of our audience. But if we're trying to get work for TV or doing kids music, it can help to say we've won these awards. That actually means quite a bit to people who know little about us."

For some artists, making a kids record might be career suicide in terms of ever making it back in the club world. For They Might Be Giants, it's a non-issue.

"We've been alternating kids record and grown-up records the whole time," he says. "I don't feel like we've corrupted our reputation in any way. We've always had a particular and self-selecting crowd for our grown-up material. They're maybe not as hung up on it having a kind of authenticity or cultural edginess. We sort of established early on that we were just doing this thing we liked and it wasn't going to make you a cooler person listening to it. As a result, the people who like us are not easily scared away by us doing children's music."

There have been three adult records over the past decade, the most recent being 2007's "The Else." A new album is in the works that may not see the light of day until 2011, in part because the band has to be careful not to saturate the market.

As for the flow of the songwriting, which always seemed to come so easy for the band, Mr. Linnell says it's gotten a little tougher as the years have passed.

"We're always working to do something new and we don't want to repeat ourselves. In that way it's hard to write material that's up to your same old standards. I think being very honest about it, it's a reality to be tuned into. We do have a lot of ideas and we're excited by the good ones, but we still have the same number of bad ideas as we did in the old days. We don't want to start including those."

Critics Andrew Druckenbrod and Scott Mervis talk about music on "The Beat," available exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.