"Checkers," an orphan whose real name is Judy, travels with her Uncle Edgar Connell, who prefers a life on the road racing horses to settling down with his longtime fiancée, Mamie Appleby, who takes care of Checkers during the school year. After they hire Jimmy Somers, a rough, woman-hating adolescent, to ride their prize colt, Blue Skies, they enter the colt in a claiming race, hoping to raise enough money to repay Mamie for Checkers' room and board. Ed discounts the risk that someone will claim Blue Skies, whom they have purposely held back in previous races to build good odds, but George F. Green, whom Ed earlier swindled, recognizes the horse and puts in a claim for $1,000. During the race, Blue Skies falls and breaks a leg. Green is about to shoot the horse, but Checkers pleads for his life, and Green offers to return the horse for a refund of his money. Ed's initial refusal of the offer provokes such a torrent of tears from Checkers that he acquiesces. When Ed, Checkers and Jimmy arrive at Mamie's farm, they find Tobias Williams, a widowed banker, courting her. Mamie, who loves Ed, but will not marry him until he gives up racing, is angry that they have brought the injured Blue Skies, but she gives Ed one more chance to settle down. While Blue Skies' leg heals, Jimmy falls for Tobias' snooty daughter Sarah and works after school in Tobias' bank. When Ed learns from Checkers, who is extremely jealous of Sarah, that Tobias has practically proposed to Mamie, he plants oil on Mamie's land and arranges for Tobias to find out about it. Mamie is then outraged when Tobias proposes without letting on that he knows about the oil, and she breaks his proffered vase of flowers over his head. Tobias fires Jimmy, who now forgets Sarah and joins Checkers to prepare Blue Skies for the upcoming State Fair Derby. Upset by the close call with Tobias, Ed has decided that if Mamie will have him, he will give up Blue Skies. However, when he learns that Mamie has borrowed $10,000 to proceed with drilling for oil, Ed agrees to race the horse to win the $10,000 first prize and sells Nellie, Blue Skies' mother, to Green for the entrance fee. Meanwhile, Mamie, after learning that the oil was a ruse, is angry with Ed and perplexed because Tobias now threatens to take over the farm. To keep Blue Skies from winning, Tobias has Jimmy arrested on a trumped up charge. Learning of this, Mamie connives with Checkers to get Jimmy out of jail. At the start of the race, Blue Skies, who has been nervous and balky since Nellie was sold, is last. Checkers, however, rides Nellie onto the track, which stimulates Blue Skies to win. After Mamie collects much money from betting on Blue Skies, she and Ed embrace and plan their honeymoon.