An 11-year-old boy in Montana recently proved he has greater resolve than most adults by living up to his New Year's resolution and earning $500 from his parents as a prize.

It was a marshmallow experiment for big kids. Jonathan Sarisky's parents made him and his older brother a deal at Christmas in 2013. You can have $100 now, or you can give up soda for one year and get $500. Both boys deliberated for a few days. Take the $100 now, or hold out for more? But if they failed at what later became known as the "No Pop Challenge," they wouldn't see a cent. Jonathan's older brother Andrew opted for the sure thing. He took his $100 and called it good. But Jonathan, a sixth-grader at Sleeping Giant Middle School in Montana, had his eye on the prize.

He took the yearlong challenge, signed a contract with his parents, and savored his last soda on Jan. 3, 2014, on the occasion of Andrew’s birthday. It was Fanta Orange and he said in later interviews that he didn’t even brush his teeth for a while so that he could prolong the taste of the soda in his mouth.

For the next year, Jonathan had to avoid not only sodas, but all sugary drinks — including hot chocolate, sports drinks, lemonade, fruit juices and milkshakes. That left nothing but water and unflavored milk as his only beverage options. The terms were harsh, and included a zero tolerance policy that meant that even one slipup and Jonathan would forfeit any chance at the money. But his parents also gave him free rein to spend his $500 however he liked if he succeeded.

Jonathan said that adhering to the contract was not that hard. He just had to keep reminding his friends not to offer him soda or other drinks when they were hanging out. But it was all worth it at the end of the yearlong challenge when Jonathan's parents handed him the dough. They even made a lottery winner-style check to present to him.

Jonathan said that money made giving up sugary drinks for the whole year totally worth it.

"If it was just $100, I don't think I would have done it," Jonathan told reporters. "The price was right."

Related on MNN: