Newtown School Superintendent Janet Robinson

Newtown School Superintendent Janet Robinson holds up pictures of cards and notes that Sandy Hook Elementary School received from all around the world following the mass shooting there as she speaks about gun violence during a meeting of the House Democratic Steering and Policy Committee on Capitol Hill in Washington, DC, on January 16. (SAUL LOEB, AFPGetty Images / January 16, 2013)

Newtown schools Superintendent Janet Robinson on Wednesday told U.S. House Democratic leaders about the horrors of the Dec. 14 shooting and ended by sharing a fourth-grader's letter to House Democratic Leader Nancy Pelosi asking for a change in gun laws.

"What everyone in Newtown wants is for you to ban semiautomatic weapons and large-capacity magazines and to make everyone use guns safely," Robinson said, reading from the letter. "This is important so that a person cannot shoot many people at once, and/or injure people badly. Semiautomatic weapons and large-capacity magazines put lives at risk."

The Newtown fourth-grade girl asked that people opposed to gun control visit the town's municipal offices, which are lined with boxes full of cards and letters, and to read one card from every box to realize just how many people want a change in gun laws.

Robinson was among several speakers at a House Democratic Steering and Policy Committee hearing on preventing gun violence. Pelosi was in attendance. A video of the testimony is available at c-span.org.

"Our sense of security has been shattered," Robinson said.

Robinson said she came to Congress "to give a face to the children, the staff, the families of Sandy Hook in Newtown, Connecticut."

Robinson also confirmed publicly what a local pastor told ABC News shortly after the Dec. 14 massacre — that a student in teacher Lauren Rousseau's classroom survived by playing dead.

The superintendent set the scene by describing the town, its high academic standards, and what she called its perception as "the safest place on Earth" in the "quiet, little suburban community."

"On a beautiful winter morning in December, buses dropped off their precious cargo: nearly 500 elementary children who filed in their school with the expectations of all little children — that good things would be happening," Robinson said.

Then she described gunman Adam Lanza's actions: how he shot through a glass door to gain entry, then killed Principal Dawn Hochsprung and made his way to a classroom.

"The shooter bypassed [the] first-grade classroom on the left and began shooting in the second first-grade classroom, killing the school's permanent substitute teacher, Lauren Rousseau, and all but one child who was clever enough to play dead and didn't even whimper.

"By this time, the teacher in the third room had crammed as many children as possible in the bathroom, was trying to find hiding places for the others when the [shooter] took aim on her and her students. Vicki Soto, who was so excited to finally reach her dream to be a teacher, threw herself in front of her students. Such incredible bravery from a young, first-grade teacher."

Robinson said first responders arrived in three minutes, which she said was impressive for a town of 60 square miles of mostly country roads. Robinson said the fast response saved "innumerable lives" because Lanza had enough ammunition to kill many more in the school.

"Twenty beautiful and innocent, little first-graders were lost that day in a senseless act," Robinson said. "They were no match for a troubled person with an AR-15."