When the teachers are at bay, the students come out to play.

March break means six times as much work for a Toronto graffiti removal business.

The two Toronto franchises of Goodbye Graffiti have tackled about 300 removals so far during March break, compared with the usual average of 50 a week, said co-owner John Kalimeris.

"Students are not spending the day in school so generally during March break . . . they stay out later . . . they can cause damage later in the evening," said Mr. Kalimeris, who opened the Toronto franchises in March, 2003, after operating in Victoria for two years.

Yesterday morning he headed up to Roncesvalles Avenue, north of Queen Street West, after hearing on the morning news about the overnight defacement of 13 storefronts and a number of TTC shelters.

"Traditionally, during March break a lot of things go up in the city; break and enters go up," Detective Sergeant Brian O'Connor said. "Kids are out wandering when they want."

Four 16-year-old males were arrested and charged with two counts of mischief under $5,000 each at about 3:30 a.m. Wednesday after an off-duty police officer noticed people spray painting property in the Roncesvalles and Queen Street West area.

Police arrested four youths who live in the area after finding them with spray-paint cans and markers that had recently been used.

But graffiti culprits are a slippery bunch. "They rarely catch them, which [makes the arrests] quite impressive," Mr. Kalimeris said.

Guardian Pharmacy on Roncesvalles was tagged during the spree, and is hit as often as once a month, said manager Rudy Persaud, who would like to see the guilty parties pay for the paint and labour needed for cleanup.

"It makes [the pharmacy] look unpresentable," he said.

Ted Buniakowski, owner of Queen Syrena Travel, said graffiti incidents have increased over the past year. He noticed the tags on his storefront when he got to work at 9 a.m. yesterday. He pays about $300 every two to three months to paint over it.

"We've been living with this graffiti for quite a while . . . are we likely to notice something new?" wondered Iwona Salapatek of Solarski Pharmacy and Postal Outlet, as she walked outside to check the storefront.

"Tagging has gotten progressively worse in this area," Det. Sgt. O'Connor said. "It's not just 11 [Division]; it's all over the city."

Mr. Kalimeris, whose business has tripled since last summer, said "the majority of the problem is downtown."

But it is "spreading to suburbs in Etobicoke, Scarborough, and North York," he said. "Areas that don't clean up as fast get tagged more frequently."

He added that neighbourhoods such as Chinatown, Bloor West Village and Lower Spadina are hit frequently.

The typical graffiti artist is a male, between the ages of 14 and17 who is part of the skateboarding culture, Mr. Kalimeris said.

"They're trying to develop an identity . . . they want to be seen, they want the tag to be seen."

And these days there are new forms of self-expression -- there's scratchiti (scratches on glass surfaces), giraffiti (graffiti in high places that are harder to remove), and acid-etching on glass, which is more widespread in Western Canada but slowly coming to Toronto.

Goodbye Graffiti is working on a process to buff away acid-etches, but usually, the glass needs to be replaced, Mr. Kalimeris said.

"It's pretty disturbing because you can see results in the neighbourhood," Det. Sgt. O'Connor said. "It certainly affects the quality of life and the physical look of the area, and can create an atmosphere that the area is not well taken care of."

The four males, who cannot be named under the Youth Criminal Justice Act, have been released and will appear in court some time over the next two weeks.