What could have improved the validity of Mrs. Andrews' test?

Using mixed colors for the shapes during testing could have improved the validity of Mrs. Andrews' test because it allows for a more comprehensive assessment of the students' understanding of the concepts being tested. If the test was originally only using one color for the shapes, students might not be fully engaged or may misinterpret the assessment if they associate certain colors with specific meanings or instructions. By incorporating mixed colors, the test could more effectively measure the students' ability to recognize and differentiate shapes independent of color bias, ensuring that their responses are based on their actual knowledge of the shapes rather than their perceptions influenced by color. This enhances the overall validity by ensuring that the test assesses what it is intended to assess, providing a clearer picture of the students' understanding of the subject matter.