How do Jess and Leslie feel about helping Leslie's father fix up the house?

While Leslie is excited to work on fixing up the house, Jess resents it at first when he is not included. Later, he comes to enjoy the process when Leslie tells him to join her and Bill.
Leslie's father, Bill, is often busy in Washington, DC, because he writes political books and is in the process of finishing one. When Jess is first thinking about Leslie and her parents in the beginning of the book, he thinks about how Bill promised he would soon stay home and help fix up the house instead of traveling.
Later in the book, this promise comes true. Leslie gets to help her father fix up the house. Katherine Paterson writes the following about Leslie:

She was crazy about fixing up that broken-down old wreck of a house. She loved being needed by her father. Half the time they were supposed to be working they were just yakking away. She was learning, she related glowingly at recess, to "understand" her father.

Jess does not relate to the need to understand one's parents. He thinks Bill "ought to have friends his own age and let her have hers." He misses Leslie and, because she is too distracted to go to Terabithia, he does not see the point in going alone. Leslie, Jess thinks, is what gives the place its magic. He does not like staying home because he does not want to do chores or play with dolls with his little sister.
When Leslie notices Jess's feelings, she asks why he does not like her father. Jess says Leslie is always busy—never admitting to disliking Bill. Leslie invites Jess to join them; once he does, Bill praises the job Jess does on the house. 
Once he is involved, Jess also enjoys the process of fixing up the house. It keeps them away from Terabithia for a month.