San Marcos — They’re big, they’re bright yellow, they have flashing red lights and now they have their own police officers to help their little passengers stay safe.

San Marcos Police Officer Daniel Castillo rode a San Marcos Consolidated School District (SMCISD) school bus recently to help catch drivers who don’t stop when the school bus is loading or unloading students.

State law requires approaching drivers to stop when a school bus is stopped and operating a visual signal, like red flashing lights or a stop sign, SMCISD officials said.

Bus driver Barak Fletcher said he sees cars pass his bus illegally every day.

“They’re (drivers) focused on what’s in front of them,” he said. “It’s like a horse with blinders on.”

When children enter or exit a school bus, vehicles on both sides of the road are required to stop.

The rule also applies if a highway is divided only by a left turning lane and the roadways are not separated, said SMCISD officials.

On a highway with roadways separated by an interview space or a physical barrier, only vehicles on the same side as the bus must stop.

During last week’s sting operation, Castillo worked with two motorcycle officers, who were close by to ticket drivers who passed the bus illegally.

“We stopped a lady on Thorpe Lane. She didn’t even stop and we were stopped for quite some time,” said Castillo.

Bus monitor Henrietta Rodriguez was walking a boy to an apartment complex when the oncoming vehicle sped past.

Rodriguez does not always walk children across the street, but “sometimes we just don’t have a choice but to cross,” she said.

“If a little kid drops something, that’s it,” Fletcher said.

He said he witnessed a three-car accident caused by a vehicle who stopped suddenly after seeing a stopped bus at the last minute.

In September 2008, a bus loaded with three and four-year-old pre-kindergarten students was stopped at a stop sign on Hwy. 21 when a pickup truck crashed into the back of the bus. Students were evacuated and no one was injured.

“Highway 21 is one of our scariest locations,” SMCISD transportation director Ernest Martinez said. He said major roadways, like Aquarena Springs Drive, Hopkins Street and highways are the most dangerous.

Fletcher tries honking his horn and putting his hands out the window to signal drivers to stop and sometimes he explains to drivers why they need to stop.

“When I try to explain to them, they say they didn’t know,” he said. “I’ve even had them wave back to me.”

Castillo said some drivers mistake school buses for Texas State tram buses, which make frequent stops on busy streets near the university campus.

“They don’t have to stop for the tram, they confuse the Texas State tram with school buses,” he said.

Officers will ride an SMCISD bus about once a month, Castillo said, to help prevent illegal passing.

The maximum fine for illegally passing a school bus is $1,000. Municipal court officials said the average fine for this offense in San Marcos is $250.