This Concept Assessment / Test Prep Activity directly supports NGSS Standard MS.LS4.6: Use mathematical representations to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time. The purpose of this 45 minute, 5E investigation is to understand and explain how natural selection drives changes in traits within a population, and how environmental factors and survival affect trait distribution. In this lesson, students will engage with concepts related to natural selection by reading passages on how traits within a population change over generations due to environmental pressures. They will answer multiple-choice questions based on key concepts to reinforce their understanding of how traits become more common or less common due to survival advantages. This activity includes 25 multiple-choice assessment or test-prep questions based on five key objective-based concepts. This package includes a lesson plan, instructor activity guide, students activity guide, response worksheet, answer key, and digital response worksheet. Just print, prep, and it’s ready to go.