It’s a sold-out rock show. The crowd is lining up at the doors more than an hour beforehand.

It’s Staff Infection’s biggest gig of the year. The band opens with “Smoke on the Water,” awash in fog, lasers and strobe lights, and throughout the two-hour set, the crowd of 1,000 breaks into ecstatic applause and wolf whistles between numbers. They close with “Stairway to Heaven.”

Sound too cool for school? Not quite.

Staff Infection is made up mostly of teachers at Anoka High.

The band got its start in the mid-1990s, although one of its first performances drew mixed reviews. At a pep fest, Staff Infection got the students so revved up that band members began crowd surfing.

“We played one song, ‘Proud Mary.’ Our principal thought we would lip sync. They were shocked when we tore into that song and rocked it,” said lead singer and guitarist Pat Coffee, who teaches industrial arts. “They came up afterward and said, ‘That’s the last time you’ll be playing pep fest.’ ”

The band has since had its hall pass restored. Each year, they play a pair of charity concerts at the school. They also perform at local bars on their tongue-and-cheek “It’s a Small World Tour.”

“They’re awesome,” said Principal Mike Farley, who wasn’t principal during the pep fest episode. “I don’t know that I’ve ever been at another school where they’ve had [a rock band].”

So you want to be a rock and roll star

Coffee is the founding member of the band, which now has nine members, including its sound engineer. He grew up in a musical family and has played in several bands over the years.

In the mid-1990s, Coffee shared an office with fellow shop teacher Roger Hofmeister, who had played drums in a rock band.

“I found out he could handle himself,” Coffee said. He asked Hofmeister if he wanted to form a band, then recruited other faculty members who had musical backgrounds.

“I got up at a faculty meeting and I made an announcement. The whole faculty started laughing,” Coffee recalls.

But the band slowly came together. Science teacher Scott Birklid, who plays guitar and sings, was an original member. He has some showbiz in his genes; his grandfather was 1940s Fargo, N.D., radio star Lars “Texas Ranger” Birklid.

“It’s so much fun,” said Birklid. “Am I actually doing this? It’s always going through my head. It’s a very out-of-body experience.”

The faculty band played that first pep fest. Initially, there were some nerves about performing in front of their students, but the kids ate it up.

“They were going crazy. We were told we could never do that again,” Birklid recalls. “It was really fun and it became addictive.”

Dialing it down

Chastened, the band stuck to faculty holiday parties and the occasional retirement party for a while.

They eventually started playing some paid gigs at Northwoods Bar & Grill in Nowthen and Serum’s Good Time Emporium in Anoka. They also play the occasional wedding or private party.

When customers ask who’s playing, Northwoods staff will mention it’s a band of teachers. Oftentimes, customers wait around to see if the teachers can hold their own onstage. They’re not disappointed.

“They’re very good and a lot of people come in to see them,” said Northwoods bartender Kaitlin Walsh.

They’ve developed a healthy fan following, including parents and former students.

“I suppose you have a perception of a teacher being straight-laced, and then they are out there having fun. They are a fun band,” said bar owner Gary Serum.

The band got its name as part of a contest at a faculty party.

“There were some great ideas and some filthy ones,” Coffee said.

It came down to Staff Infection and Class Act. Coffee chose the edgier one.

Staff Infection eventually returned to school, playing the pep fest on the first day of school.

Members of the music faculty, reluctant to sign on because of their hectic student concert calendar, eventually joined the band. They added a brass section, allowing the band to do some songs by Chicago; Blood, Sweat and Tears, and Van Morrison.

High school band director John Lace plays trumpet and sings. Orchestra director Michael Halstenson plays keyboards. While many members of the band individually write original music, they mostly perform classic rock covers. Crowd favorites include “Brown-Eyed Girl” and “Moon Dance.”

Symphonic Rock

The biggest gig of the year is the annual Symphonic Rock concerts, a two-night fundraiser with choir and orchestra students at the high school auditorium. This year’s edition took place earlier this month.

The students and Staff Infection, mostly in their 50s and older, belt out two hours of rock hits, including “Bohemian Rhapsody” and “Don’t Stop Believin.”

The shows have become so popular that District Superintendent Dennis Carlson joins the band for a Pink Floyd number, singing lead vocals and guitar, and plays the harmonica for Billy Joel’s “Piano Man.”

Performing with the students is “so groovy,” Coffee said.

They change the music lineup each year.

On stage, the teachers look relaxed and cool. Between songs, they banter and joke a bit. The more than 100 concert choir and concert orchestra students on stage performing with them are beaming.

“They’re really smooth,” said parent Tracie Hanson, whose daughter Stephanie Nielsen is a junior. “It’s my favorite concert of the year. It’s really fun for the kids to see their teachers outside the teacher role, playing rock-n-roll and dancing.”

At school, Mr. Coffee is all teacher, wearing a polo shirt with a large key ring hooked to his belt. But on stage with a guitar and microphone, he becomes a rock star.

“No doubt about it. After Symphonic Rock they are like “Oh Mr. Coffee, I never knew!”