May 26, 2011 -- Seventeen-year-old Elliott Kersh is helping his father gather what's left from their house in Joplin, Mo.
Elliott has the weight of the world on his mind right now.
"It's so catastrophic," he said. "My friends, I'd say 80 percent of them don't have a house anymore."
And many, like him, are dealing with memories from Sunday - when they rushed from the rubble of their own homes to help neighbors crawl out from theirs.
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"There was this lady I saw bent over, she got off work at the mall, and couldn't come home in time," said Elliott. "But her husband and two sons had taken shelter in the basement which was collapsed in and I had to pull out, I had to pull out her dead husband and her two sons, which were hardly identifiable at the time, but, I, I had to pull those out for her."
"I don't know what I would have done if I was her, because that's your whole family," he added.
Every day since, he has pressed his dad to let him get out here and help.
"He's up, calling me in the morning, saying what are we going to do today, let's get going," said Richard Kersh of his son. "And, you know, that's a blessing."
There are hundreds more teenagers here, just like Elliott, who were changed on Sunday.
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"We started pulling people out of houses, and covering up bodies and stuff, and just doing what we could to help people," said Mitchell, 18. "A lot of destruction, dead bodies, more than I ever care to see for the rest of my life."
"Joplin was gone," said Geordan Green, also 18. "I didn't know what to do except to help people."
"My friend Geordan here, he had to hold me because I couldn't stop crying, I couldn't stand up," said Mitchell.
In trying to make their way through all of this, to find something, anything good, many are discovering that the "good," is in them.
"Seeing people that are helpless just hurts you," said Geordan. "And I knew if I felt that way, I'd want people to care about me. So I don't want to be a selfish person anymore."
"If I saw somebody without a shirt right now, I'd take it off my own back and give it to them. If somebody didn't have shoes I'd give it to them," said 16-year-old Gibson.
"I really took a lot of things for granted before this," another boy named Brett said.
Elliott chanced upon a student in a grocery store, someone he'd often fought in school.
"But we about broke down crying in Food 4 Less when we were trying to get some ice," he said. "When we saw each other, we were just so happy to see each other, it was just so comforting."
They have a great capacity -- for hope.
"This summer I'm going to help rebuild Joplin the best I can. I'm not the most handy guy there is, but whatever I can do to help," said Geordan.
"I think we have the potential to be great again," said Spencer Ming.
"We still all have each other, everybody that's left," added Mitchell. "So we can fix it."
The adults around them are rediscovering how good it is to be with them.
"Oh yeah, I mean I love him to death, and he's a strong young man, and I'm very proud," said Kersh. "I just can't say enough."
They know it's going to be a tough summer -- and that the memories will linger.
"I need to help here and my family's here," said another teen, Olivia. "But in a way I want to leave, because of all the painful things I've seen and, oh, I'm so sorry."
They believe they are up to it, that what they do here will truly matter.