This is one of 25 assessment probes from the book, “Uncovering Student Ideas in Science, Volume 2: 25 More Formative Assessment Probes”, by Page Keeley, Francis Eberle, and Joy Tugel. All assessment probes in this collection are aligned to a particular science concept and field-tested by several teachers in classes of diverse student backgrounds. The “Giant Sequoia Tree” formative assessment probe elicits student ideas about the transformation of matter through photosynthesis in plants. The probe presents a multiple choice question asking where most of the matter in a giant sequoia tree comes from, and then asks students to explain their thinking. The probe could be used to present the phenomena of plant growth and photosynthesis and to reveal students’ initial ideas about this concept. The probe could then be revisited at the end of a unit in which students investigate plant growth and carbon cycling.
An assessment probe is a purposefully designed question that asks students to provide a two-part response. Part one consists of a selected response, and part two asks students to provide an explanation. The probe is designed for students at elementary, middle, or high school grade levels. This format helps teachers identify students’ existing ideas about phenomena or concepts, which can help inform further instruction. Assessment probes can also be used to engage students, encourage thinking, and promote sharing of ideas. When implementing probes in the classroom, the authors suggest using the probe to encourage teacher-student, student-teacher, and student-student feedback on learning. Each probe is accompanied by teacher notes that include information on the purpose of the probe, related science concepts, an explanation of all answer choices, curricular and instructional considerations, suggestions for administering the probe, related standards (National Science Education Standards, 1996), related ideas in Benchmarks for Science Literacy (AAAS, 1993), related research, description of common student misconceptions, suggestions for instruction and assessment, and related NSTA science store publications and journal articles.