On the same day that thousands of New England teens gathered in Boston to talk about ways to stop bullying, a much smaller and younger group gathered at Hadley School for the same reason.

Hadley third- and fourth-graders sat on the gym floor Tuesday to hear Hadley parent Megan Kelley Hall talk about bullying.

The parent has helped assemble a book called Dear Bully, an anthology of personal stories on bullying.

The mom told the Hadley children they might want to read the book when they get to middle school but that does not mean that some of them aren't dealing with some of the same bullying experiences now.

She talked about clear cut instances of bullying — pushing and shoving and kicking — and more subtle instances.

She also talked about ways to respond and prevent bullying.

The children laughed as a class when Megan and her daughter, a Hadley student, performed skits that demonstrated the subtle bullying.

In one skit Megan, playing a classmate, walked up to the victim and, smiling, complimented her on her outfit.

Megan then turned away and said, in a low-voice aside: "Don't tell her I told you but (she) is a little cuckooooooo."

The bully folded her arms and rolled her eyes.

In short, the mom told the class, "Bullying is when you hurt people's feelings — intentionally."

It need only happen once to be considered bullying, she said.

Lots of times bullies can be friends, she said.

She told the children they need to respect themselves and ask themselves: would they want someone to talk to them that way?

She encouraged the children to walk away from bullies and tell an adult or have a friend tell an adult about a problem.

In the end, she said, everyone has the capacity to be a bully or to build people up.

"So you have a choice," she said.

It's much better to dispose of bullying now, in elementary school, so they do not have to deal with a bigger problem in their teen years.

On Tuesday at Northeastern University 4,000 middle- and high school students, some from Swampscott, attended a conference called Stand Up to bullying where students talked about youth bullying.