Not only do the actual suicides of some teens encourage others who may already be thinking about it, she said, some studies have suggested that intense media coverage spurs others.
"It's like drugs," she said. "You pass around drugs and that encourages other kids to do it."
But authorities also have to be careful not to keep it so close to the vest that no information gets out.
"People do need to know what's going on," she said.
Kaslow said warning signs can include depression, giving away possessions, deterioration in both academics and social activities, general disinterest and substance abuse. Some teens, she said, will even go as far as to send out a text message or an e-mail to a friend to say goodbye.
"Often what happens is teens feel like things aren't going to get any better and no one understands them," she said. "There's so much much emotion."
Suicide by train is not very common among teenagers, she said. But it serves its purpose for kids who are serious about taking their own lives.
"A train is violent. There's no question about it," she said. "It works."
Kaslow said she was, coincidentally, in Palo Alto two weeks ago for an unrelated talk on depressed teenagers when -- not knowing about the prior suicides -- she mentioned leaping in front a train.
She was then stunned to learn about what had happened there in the spring and summer.
"Parents are extremely affected by this right now and they need help, too," she said of Palo Alto. "How do you know your kid isn't going to be next?"