Nothing satisfies a teacher more than seeing a smile of delight on students' faces when they turn over their test paper to reveal a successful score. In today's world of standardized testing, some elementary science teachers may struggle to help students move from active engagement in hands-on science experiences to high levels of achievement on paper-and-pencil tests. Consequently, that smile of delight is not seen often enough. However, these authors have discovered that one key to raising achievement scores is to carefully weave formative assessments throughout each phase of the 5E Instructional Model. The 5E Model is a lesson cycle based on inquiry and constructivism. The 5E Model phases are engage, explore, explain, elaborate, and evaluate (Bybee et al. 2006). The 5E Instructional Model is relevant to all age levels, as is the process of using formative assessments at every phase of the model. Specific examples of formative assessments given in the following 5E model are appropriate for grades 2 through 5, although the audience for the mixture and solution activities would be grades 4 and 5.