After the mass shooting at Sandy Hook Elementary School in December, every teacher, principal, superintendent and parent looked around and wondered: Could it happen here?

It may be hard to stop an armed intruder intent on doing harm, but after the tragedy in Newtown, Conn., that took the lives of 20 first-graders and six educators, schools looked at their locked doors and security cameras and convened their safety committees to see what more they could do.

The answer: Not much.

The steps taken after the 1999 massacre at Columbine High School in Colorado, where 12 students and a teacher were shot to death, led many districts to look at school security with a critical eye for the first time. That incident led directly to the intercoms, buzzers and staffed entry desks now commonplace in school buildings.

But Newtown has led to schools making sure students are better prepared in case of an emergency and a refining of security policies that already restrict access:

• Union East Elementary in Cheektowaga is requiring parents to state their name, their child’s name and their reason for being there before getting buzzed into school, and to show ID when inside to pick up their children.

• Newfane schools are adjusting automatic locks on school doors and compiling “go bags” at each school with information for first responders.

• The Williamsville district is hiring 13 new part-time monitors for schools.

“Its important we were able to do that,” Superintendent Scott G. Martzloff said. “That’s why school districts have a fund balance. You have to have money available in these types of emergencies.”

The temporary monitors will work five hours a day, acting as another set of eyes and directing visitors. Existing staff will fill in the rest of the day, he said.

“This isn’t somebody who could stop somebody with a weapon. It is another layer of security when school is in session,” Martzloff said.

Whether the new positions will be put into next year’s budget has not yet been decided, but the district also is adding more cameras.

Meanwhile, students already are seeing more drills in school, not only fire drills, but lockdown, lockout, shelter-in-place and evacuation drills.

In a lockout, daily activities continue in the school, the doors remain locked, and staff members meet visitors at the door, keeping them outside. Schools could use this if, for example, there were a bank robbery in the area with a suspect on the loose.

Students practice the lockdown drill in case there is an intruder in the building. Children stay in their locked classrooms with the lights off, quietly huddling in a corner or a closet. Teachers try to make the children as invisible as possible, said Newfane Superintendent Christine J. Tibbetts.

The key for children is to practice, so the first time they are told to huddle in the corner, it will not be when there is a gunman in the building.

“We tell them we’re practicing in the event we want to hide the children from anybody who might be a bad person who is in the building,” Tibbetts said.

Students would shelter-in-place, staying in the school, if there were a threat outside the school grounds, such as a weather emergency or chemical spill, and school was the safest place for them. Schools also have evacuation plans, to take students to alternative locations in an emergency at the school.

Niagara Falls city schools already have monitors and school resource officers. But in the wake of Sandy Hook, the district looked at every school again.

“We made sure everybody was on high alert,” Superintendent Cynthia A. Bianco said.

That meant making sure staff members knew the procedures and practiced those procedures. The district had many drills, but they were all announced, she said. Late last month, the district notified parents that they will be having unannounced drills. The schools will contact parents after the drill, so they don’t worry if they hear students were evacuated.

Cheektowaga police, like many local agencies, talked with principals and superintendents in the town after the Newtown shooting, said Capt. James J. Speyer Jr. The town has had an officer-school liaison program since 1998. Speyer said police did not change the plans at Cheektowaga schools, but they have taken steps to prevent incidents and to handle those that might occur.

One of the first rules: “You have to make sure your staff and faculty know what the plan is.”

Cheektowaga police have trained in all the schools in the town, so they are familiar with the layouts. There are cameras at the schools hooked into the police dispatch office, so if police are called to the school, dispatch officers let them know what they will find when they arrive.

The Police Department also operates an anonymous tip line, and some districts have tip lines of their own. Police will complete a threat assessment on reports concerning those who might harm themselves or others.

“Nobody wants to respond to a situation; we want to prevent a situation from ever occurring,” Speyer said.

After Sandy Hook, the Newfane district also began compiling “go bags” at each school with information for first responders, such as diagrams of the building, class lists and telephone trees with contact information.

At Cheektowaga Central’s Union East Elementary School, parents are not allowed into classrooms unless they are there to volunteer, and staff members are much more visible outside and inside the school before and after classes.

“Everywhere a kid goes, they’re going to see an adult,” Principal Gretchen A. Sukdolak said.

The district also is being more vigilant about requiring parents to state their business before being allowed entry into the building, which could cause a delay.

“People don’t complain because they know why we’re doing it,” Superintendent Dennis M. Kane said.

Despite the ongoing refinements since Newtown, and the more radical changes after Columbine, it’s difficult to protect against someone intent on harming children who feels he or she has nothing to lose.

And no building can be 100 percent protected, said Donald A. Ogilvie, superintendent of Erie 1 Board of Cooperative Educational Services. Perhaps the most important factor is an alert, responsible staff.

“I would rather have a building full of adults who are aware of the emergency response plan, who are conscious of what is a normal part of routine, with internal communication,” Ogilvie said. “I’d rather have that network than any electronic device lulling me into thinking I had absolute security.”