The National Center for Education Statistics monitors many aspects

The National Center for Education Statistics monitors many aspects of elementary and secondary education. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 randomly chosen students found that this figure had grown to 32%.

Is this evidence of a change in education level among mothers? Check the assumptions and conditions.