The setting is tranquil. Smooth water with trees lining the banks of the river.

The effort is intense. Eight high school students in a sliver of a racing shell straining together, working as one toward a goal.

The contrast is what attracted North Allegheny High School senior Michelle Weaver to the school's rowing team.

"It's a completely unique sport. It looks so pretty [when you're out on the water], but it is the most intense sport," said Weaver, one of the team captains. "You have to be so physical."

Rowing, or crew as it is often called, has become popular at a number of area high schools. And those interested in the sport who attend schools that do not have rowing programs can be found on teams at Three Rivers Rowing.

"We have high school kids who come down to row on club teams from 15 or so different schools," said Rick Brown of Three Rivers Rowing, which has facilities at Washington's Landing and the Millvale Water Park on the Allegheny River. "It is still a relatively new sport for Pittsburgh, but it is growing each year."

High school teams will get an opportunity to show what they can do tomorrow at the Head of the Ohio. Participants from more that 100 organizations, including colleges and high schools, will take part in the event on the Allegheny River.

The 2.8-mile course starts on the Allegheny near Washington's Landing and ends just before Heinz Field. Teams will race against the clock in a variety of classifications. There are 16 races for high school competitors.

The first race is scheduled for 8 a.m. tomorrow with the final one at 4:20 p.m. Figuring out winners in each category could take a while.

Head races are, for the most part, held in the fall. Sprints races, which are head-to-head competitions where the first shell to the finish line wins, are in the spring.

"This [Head of the Ohio] is our first competition of the year," said North Allegheny coach Mike Bergen, who has guided the team for two-and-a-half years after coaching at Central Catholic and Allderdice. "The spring season is typically more popular.

"In head races it's like 'I don't know ... we'll have to see how we did when we get back to the boat house.' I mean, you have an idea because you pass other boats, but you don't know."

Still, he said the races tomorrow offer parents and other relatives an opportunity to see team members in action.

Rowing, at the high school level, is close to a year-round activity.

There are practices on the water in the spring, summer and fall. When the weather is bad there is weight lifting and workouts on rowing machines.

Having strong legs is a must.

"I don't think people understand [how much] you use your legs," said Weaver, who hopes to row in college. "A lot of people say, 'Oh, you go canoeing.' They don't understand how much you use your legs."

While there are races for singles and doubles, shells with four and eight rowers are more identifiable and tougher for athletes to master.

"Having eight people do the same thing up to 500 times is a tough thing," North Allegheny senior Dan Jeffries said.

Bergen pointed out that in rowing there is an event for just about everybody who is willing to put in the time and effort.

"We don't have as many weight classes as, say, wrestling, but have a lot of levels from JV to varsity to novice and we have that for boys and girls," he said. "And we'll take the biggest of the big, within some limits, to the smallest who can be a coxswain."

And rowing, at the high school level, is a do-over sport.

"A lot of really athletic kids who played basketball or football but weren't playing much get into rowing," North Allegheny senior Jim Rectenwald said. "In a lot of other sports you can't start over, but in rowing you don't get into it until you get to high school.

"It has a combination of endurance and strength you just don't see in other sports."