Inside Miss Amber's preschool class in Vancouver, morning story time is punctuated by sneezes and coughs. But nothing stops the spread of sickness like simple handwashing, according to Dr. Shelley Sanders, with Providence, St. Vincent Medical Center.

"We think that is the most effective way to prevent cold and flu infection," said Dr. Sanders.

It's a lesson the preschoolers practice often.

"We wash our hands before we eat, after we eat after they go to the bathroom after they cough or sneeze in their hands," said teacher Amber Moreau. We wanted to know if the kids are getting their hands clean enough to keep from spreading germs.

The kids slathered their hands with a special glow lotion. "And what do you see on there?," asked Moreau. "Germs," said one of the students.

The kids washed their hands with soap and warm water to see how well they get rid of the germs. The black light showed where the kids missed. Six of the eight students are sent back to the sink.

Most of the kids neglected the areas around their fingernails, between their fingers and wrists.

It's not uncommon, said Moreau, to send the kids back for a second or even third washing. But she says the kids often don't understand why they have to do it again. She hopes the glow test will helped them to understand.