The massacre of 20 children at Sandy Hook Elementary School in Newtown, Conn., has forced school administrators throughout the country to take a close look at security measures.

According to authorities, 20-year-old Adam Lanza entered the school at about 9:40 a.m. local time where his mother, Nancy Lanza, may have worked as a teacher.  Six adults at the school were also killed, including Principal Dawn Hochsprung. Police say before arriving at the school, Lanza allegedly shot and killed his mother at her Newtown home.  The gunman is said to have died at the school from a self-inflicted gunshot.

"You're just so shocked," said Michael Harano, the longtime principal at Washington Middle School in urban Honolulu. "Then of course your mind races to what would happen if something like that happened here."  

Washington Middle is a good example of how difficult it is to safeguard a school from intruders. The nearly 14-acre campus is surrounded by four busy city streets, with at least two entrances each.

“While we monitor people coming and going, it's not easy,” said Harano.  “I would say it's virtually impossible if someone was intent on coming on campus, sneaking on campus, they could find a way.”

The school has surveillance cameras, walkie-talkies and two security guards, but educators must always weigh the cost of such safeguards against the priority of educating 820 kids in grades 6 through 8.

"Our budgets have all been cut, so anything that we might use for additional security at this point in time, I wouldn't have the funding to be able to do that," Harano told KITV4.

Instead of turning schools into virtual fortresses, administrators in Hawaii focus on how teachers and students respond to violence, in particular, an active-shooter scenario like what played out in Connecticut.

"So, hopefully the training kicks in and people respond the way they're supposed to; keeping kids and staff safe is the priority," said Harano.

Washington Middle conducted such a drill in 2010, which featured Honolulu police simulating two active shooters roaming the seven-building campus. Teachers are instructed to bolt doors, turn off lights, and cover windows to keep kids from being seen by anyone intending to do harm.

Honolulu Police Chief Louis Kealoha said in a Friday morning press conference that his department works closely with the Department of Education's Safety, Security and Emergency Preparedness Branch.

"We have certain contingency plans already in place, and it's always being refined," said Kealoha.  "In case something like this happens, (our Specialized Services Division) has been training, and has been training for a very long time."

Some have suggested Hawaii schools should hire retired police officers who can legally carry concealed firearms. However, Harano said he would be against such a move, since there are too many variables involved.

"I would not want to have a gun on my campus, even if it were in the hands of a trained security (officer)," the principal said. "I would trust the police to respond in an emergency situation as fast as possible to get help to us."