Which of the following is NOT a characteristic the students would have learned about coordinate planes?

Understanding the properties of the four quadrants of a coordinate plane is essential for interpreting graphs and plotting points. In Quadrant 1, both x and y values are positive, which is a fundamental characteristic. In Quadrant 2, x-values are negative, while y-values are positive. This means that Quadrant 2 cannot contain only positive values—this is a misunderstanding of the quadrant's characteristics.

Quadrant 3 is characterized by having both x and y values as negative, while Quadrant 4 has a positive x-value and a negative y-value. Therefore, the correct answer highlights a key point about the coordinate plane: Quadrant 2 cannot contain only positive values, making it the statement that is not accurate among the options provided.