Is it permissible to use money exceeding the cost of transportation designated by the father to buy books, school supplies, or lunch, with the father's knowledge and consent if he were informed, but the son prefers not to inform him?

It is not permissible for a child to take money from his father except with his permission. What you did by using the remaining rental money for purposes other than what it was designated for, without the father's permission, is not permissible. You must repent and return the money unless the father forgives it. However, it is permissible to take from the father's money secretly, without his permission, if the father is stingy in providing the obligatory sustenance, such as food and clothing, for which the father is responsible, based on the hadith of Hind: "Take what is sufficient for you and your children in a reasonable manner."