How could Mrs. Andrews ensure that her test assesses knowledge of attributes rather than colors?

Using monochromatic shapes is a highly effective strategy for ensuring that students' test results assess knowledge of attributes rather than colors. When shapes are presented in a single color, it eliminates any influence that color perception may have on student understanding and responses. This approach focuses purely on the geometric or qualitative attributes of the shapes, such as their size, number of sides, or angles, ensuring that the assessment accurately measures students' knowledge of these features without the potential distraction or influence of varying colors.

In contrast, allowing students to pick their preferred shapes, letting them choose their own colors, or providing a color guide could introduce bias based on personal preferences or color recognition, which detracts from the focus on essential attributes. These methods could lead to responses being influenced more by color choice than by an understanding of the shapes themselves, making monochromatic shapes the optimal choice for this type of assessment.