What is Dave's conflict in "The Split Cherry Tree"?

Dave's conflict is with his father. After Professor Herbert punishes the boys who have split the cherry tree in Eif Crabtree's orchard, Dave is worried about how he will explain what has happened to his Pa.
When Professor Herbert has the boys pay for the tree that has been damaged, Dave does not have the money, so he asks his teacher to just whip him with a switch and let him go home early so he can do his chores on the farm. But, Professor Herbert tells Dave that he is too big to whip. As explanation, Dave replies that his father "makes us mind until we are twenty-one years old" and this includes whippings. As he sweeps the school room floor, Dave worries about what his father will do to him when he comes home. He tries to think of what lie he can tell.Then, after Dave arrives home after seven o'clock, his father asks, "What in the world has kept you so?" Dave tells the truth, but Pa wonders; therefore, he declares that he will visit Professor Herbert.
When Pa visits the school, his preconceptions of what Professor Herbert and the methods of teaching are like are soon dispelled as Herbert takes Luster Sexton around the school, demonstrating various things to him. But, Professor Herbert also learns from Mr. Sexton, and a mutual respect between the two men is established. Finally, Pa helps Dave sweep; as he does so, he tells Dave that Professor Herbert is "a good man" and he adds,

"...School has changed from my day and time. I'm a dead leaf, Dave. I'm behind....I'll get a broom and we'll both sweep an hour. That pays your debt."

Dave's conflict is resolved as his father comes to understand Professor Herbert and his reason for having Dave stay after school. Pa helps Dave sweep and restores Dave's and his relationship as father and son.