Eleven-year-old Sharon Quist came home from Nibley Park Elementary Friday afternoon with two things to celebrate: the beginning of summer vacation and a brand-new bike.

Too soon, however, her celebration would turn to anger and disillusionment.Quist's name had been drawn Friday from a pool of seven candidates who had achieved perfect attendance for the school year. Her prize: a rust-colored Gary Fisher mountain bike, donated by Brighton Bank.

Excited, Quist called her mother with the good news. Then she took the bike around to show all the classes.

"It was a way for her to show what can happen when you attend school every day," said Jane Larson, Nibley Park principal.

Quist brought the bike home Friday afternoon and from then on it was in constant use, said Elsa Quist, Sharon Quist's mother.

For one day, the three oldest of Sharon Quist's six children would take turns riding the bike, even eating dinner in shifts so everyone could ride. Becca, 9, was the last to have a turn - and the last to see the bike on Saturday. She left the bike on the front lawn, and came in to have din-ner.

Less than 10 minutes later, 7-year-old Kathryn came in to report that the bike was missing."We didn't believe her at first," Elsa Quist said. "We thought she was joking. We'd had two bikes stolen in the last year, and a lawn mower stolen in the last month. We thought she was just kidding us."

The family had all the best intentions. They planned to have the bike licensed and registered Monday morning; they had been keeping the bike in the house until they could buy a lock, which they also planned to do Monday; they were careful, with one notable exception, never to leave the bike unattended.

But for all their precautions and good intentions, it only took ten minutes for Sharon Quist's perfect attendance award to be stripped from her.

"She's devastated, and angry, and sad," Elsa Quist said. "She cried, and I almost cried. It hurts to see your child hurt."

Larson was shocked when she heard the news.

"It's a disaster that someone could be rewarded for something only to have it taken away immediately. I feel really bad for her. She's a wonderful girl."

Sharon Quist had only one thing to say to the people who did this to her:

"I'm mad and I want my bike back."