There are a lot of lemonade stands popping up this time of year, with camps over, school still a week away and parents looking for ways to keep kids occupied.

But not many of them are raking in $5 and $10 bills for charity.

When Lisa Lundstrom and her girls decided to set up a lemonade stand outside Lundstrom's chiropractic office this week, Lundstrom asked them to which charity they would like to donate their proceeds, and 7-year-old Ashley knew right away: the Humane Society of the Black Hills animal shelter.

"I feel bad for all these dogs, and I want to help them stay alive," she said.

Ashley's summertime baby sitter often took Ashley and her almost-5-year-old sister, Macy, to the shelter to play with and pet the animals, and the girls fell in love with the strays.

"You just want to, like, 'Here's all my money - can I take them all?'" Ashley said.

But the girls have two dogs themselves - Chief and Aspen - and couldn't adopt every animal.

Lundstrom said, in the past week before their Montessori school starts, the lemonade stand is teaching her girls advertising, networking and math skills - sometimes all in the same sale.

Ashley has the advertising part down. When she sees someone coming down the sidewalk, she stands on her little chair and calls out, "Help support the animal shelter."

She is learning the math, even if little sister Macy isn't there yet in her banking skills.

Claudia Lingg of Denver, whose daughter is a patient of Lundstrom's, asked for three lemonades, advertised on the poster for 25 cents each. Macy told her, "Two dollars," and Lingg paid $3, saying of the girls' efforts, "Well, isn't that the sweetest thing."

They're networking with their mother's circle, netting a $26 donation from her accountant at Ketel Thorstenson down the street.

And they're being forced to use math skills. One man ordered a lemonade, saying, "I hope you have change" as he pulled out a $10.

Lundstrom walked Ashley through the steps: How much change does he get for $1? What's the difference between $1 and $10? What's his total change?

She got the right answer, $9.75, but came back from the office with a handful of bills and told the man, "I'll give you all the money, plus one extra." So Lundstrom told Ashley to slow down and count out the $9 in bills.

When the man got his change, he flipped through the bills to be sure it was the right amount, then took four or five of them, folded them in half and gave them back, saying, "Here's an extra donation."

Ashley learned early in the morning that people were feeling generous to her cause and figured out a trick that waitresses use.

"I'm like, 'Do you want your change?' They say no," so a 25-cent cup of lemonade often makes them a dollar or more.

The Humane Society of the Black Hills said the money will go to a good cause.

"That's amazing," volunteer coordinator Stephanie Hilt said when told of the girls' efforts. "It's awesome when the community, especially children, can come and help us here like that. Any small donation is helpful."

She said, if people would like to donate, in addition to cash, the shelter could use towels, blankets, bleach and working washing machines and dryers.

The girls said they plan to be back in business on Thursday morning at 902 Columbus St. if anyone is thirsty.