Ishinomaki, Japan (CNN) -- Keiko Naganuma laughs at her six-year-old son, Ran, as he takes his toy alligator and pretends it's eating their blanket in the evacuation center.
She rubs his head and looks around the school gymnasium packed with other tsunami victims.
"I'm not OK," she says, still smiling as if she's talking about the weather. "Of course I'm not. But I have another son."
Naganuma's other son, eight-year-old Koto, is missing. Koto was at Ishinomaki Okawa Elementary School the day the tsunami hit. The 108 students, as they'd practiced before, evacuated when the earthquake struck, says Naganuma.
The students had no idea the tsunami was coming. Out of the 108, 77 are presumed dead or missing. Koto is among the missing, his body still not recovered.
"Ran saw the tsunami," says Naganuma. "His brother is not coming home. So I think he understands. I can see he's pretending to be happy, so we don't worry about him."
Naganuma is joining in that game of pretend, because mourning would equal collapse. Naganuma is not just missing her son, but her mother and aunt are also missing and presumed dead.
Naganuma silently counts on her fingers the number of missing relatives. "Seven or eight," she says. It's a loss that staggers the mind but is all too common in this evacuation center.
From blanket to blanket, families recount their own losses. But it's the deaths of all the children at the elementary school that pains this community most.
At the elementary school, young fathers dig with shovels alongside rescuers. The school is a shell, its inside gutted by the force of the tsunami.
Next to the school, backpacks sit in rows, waiting to be identified and retrieved. The piles of school mementos are all mud-covered -- from the school little league team to the bats they used.
Books and crayons and worksheets lay broken in the piles, all precious memories of the children they once belonged. There's no indication where the children's bodies may be, but the intention of the families is a simple one.
"No matter what's happened to him, I just want him back," says Naganuma, who says her husband has been at the school every day. "My child should come home to me. I need to find him."
With so much work to do for these parents, there's no time to think about grieving, says aid organization Save the Children. The nonprofit group hopes to ease the onslaught of trauma, by setting up "child-friendly spaces" at evacuation centers up and down the northern Japan coastline.
As the name suggests, it's a simple place that's friendly to children and their needs. Primarily, it's a place to play.
Children can play dodge ball, jump rope and color on paper. Toys, in sparse supply in every evacuation center, are occasionally available. You can hear the results: Laughter.
It sounds so simple, says Save the Children's Shana Peiffer. But it's vital at this time, she says.
The purpose, she says, is to give the children "a sense of safety and to actually also work with the parents on how to support them on this process. It's going to be a long recovery process for children who've experienced this extreme devastation."
Miku, eight, and sister Reina, 11, play at the child friendly space in their evacuation center. They're two of the 30 survivors of the elementary school. Miku draws a pretty girl with a flower in her hair, a bright red spot on her white paper. "It's pretty," says Miku, a stark difference from the devastation of the world around her.
Keiko Naganuma is also focusing on what's bright and cheery in her world, laughing lightly as often as possible around 6-year-old Ran.
I ask her: How can you not think about what's happening?
"If I stop and think about everyone single person who's missing, I can't do anything else," she says pleasantly.
So Naganuma and her son play their pretend game of the hungry alligator eating their blanket and the illusion of ordinary life.