"This is a second pair of socks," says Rudy, as he dresses for bed in his room. "Three pairs tonight," he's decided - and "five to seven shirts."
Rudy brushes his teeth, says goodnight to his parents and walks out the back door into temperatures of -23. Then the Hermantown, Minnesota high school junior crawls into a snow cave and goes to sleep.
"You know when he gets seized by an idea he really goes for it," says Mark Hummel, Rudy's dad.
This is Rudy's grandest idea yet. He is sleeping outside every night for a year.
"It was just going to be the summer initially, but then I got to August, 'Geez, this has not been hard enough.'"
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