When Alice Garvey puts her material for school away she leaves the drawer half-open. In the next shot that drawer is closed.
At 22:53 Mrs. Garvey puts her papers in a drawer and leaves the house. The drawer is open a crack. When Andrew comes out of his room to go the the drawer, it is closed.
Near the end when Andy is studying and transfers a lamp to his study table the overhead spotlight burns on before he gets the lamp to the table.
Mr Edwards' daughter Alicia is sitting in class behind Laura Ingalls at the beginning but the Edwards family has moved to California.