Will the teacher be sinful if he leaves work during the two weeks preceding the new academic year, given that there is no significant work to be done other than attendance and signing in, and considering the workplace is 150 kilometers away?

Government employees are subject to the rulings applicable to private employees, and they must adhere to the contract, in accordance with the verse: "O you who have believed, fulfill [all] contracts." The employee is required to be present at their workplace during the agreed-upon hours, and absence is not permissible except with permission from those authorized to grant it.