Final answer:
Steven sends Renee Albert away when she comes to the house to tutor him due to his stepfather's disapproval, potentially because of racist views.
Step-by-step explanation:
Steven sends Renee Albert away when she comes to the house to tutor him because his stepfather, Wynne, disapproves of her presence. In the passages provided, it is mentioned that Wynne insults and abuses a boy who delivers a telegram late, using racist language towards the boy's sister. This suggests that Wynne holds racist views, which is likely the reason for his objection to Renee's presence as a tutor.