Their mom keeps the temperature at 66 degrees - not just to save money, but because her middle-school-aged daughters, Jane and Annie, insist, CBS News correspondent Ben Tracy reports.
"We are inheriting all the problems that we are facing so we need to start dealing with those problems now," Jane said.
The girls are part of a new generation of eco-warriors, teaching their parents about conservation and recycling.
"God forbid one of them walks in and see me getting ready to throw it in the trash they will scream at me," said the girls' mother, Leah Ingram.
The green gospel is now being preached in kids movies and even on their Girl Scout patches. Three years ago, one environmental education group was working with 150 teachers nationwide - now they are training 1,000 and their curriculum is in clost to 10,000 schools.
"They're learning in school they hear their friends talk about it. I think there is a real buzz especially with young people," said Michael Oko of the Natural Resources Defense Council.
Frances Kretschmer painted her room green and joined her school's eco club in California. She's a stickler for turning off the lights, makes her mom wash her clothes in cold water and even dressed up as a recycling bin for Halloween.
"You can recycle that costume next year."
This past Christmas, Frances convinced her parents to get a very un-traditional tree that they planted after the holidays. She didn't, however, hook her younger brother, Miles.
"I don't really like it very much," Miles said. "It's cool though."
Some of Frances' eco-sensibilities came from her grandmother, who often picks her up from school on a fuel-efficient tandem bike. Yet bringing her parents along for the ride isn't always smooth.
"I want my dad to take less showers and I want him to ride his bike to work," she said.
"She is our environmental consciences. She keeps us honest," said her mother, Charlotte Bregante.
And they are saving green - trimming $50 off the electrical bill and spending less onf the clothes Frances will only buy second-hand.
"My mom likes to do anything good for the environment that saves money too," Frances said.
That's a green lesson both parents are still teaching their kids.