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Introduction Demonstrations are time-tested classroom strategies that have been used in the teaching of chemical concepts for centuries. The goals of this manual are: to introduce educators to several common uses of demonstrations that align with current understanding of best practices for teaching science as inquiry; to provide educators with demonstrations that can be utilized in the teaching of specific chemical concepts in secondary science classrooms; to serve as a catalyst for the creation of new demonstrations and implementation strategies. Teachers are finding themselves increasingly constrained by limited budgets and dwindling instructional time. These restrictions, as well as student safety, must weigh heavily when determining the feasibility and value of instructional tools and techniques employed at the high school level. It was with these considerations in mind that the demonstrations for this project were chosen. Each exemplifies a relatively inexpensive discrepant event that can teach a chemical concept without a large time commitment or the need for sophisticated equipment or unusual chemicals. Theoretical Basis Demonstrations occur when teachers focus instruction around a particular phenomenon (Llewellyn, 2002). Llewellyn (2005) suggests that effective teachers utilize demonstration techniques when: it is beneficial for all students to witness the same outcome; a phenomenon leads to potentially dangerous or uncertain results; time or budget constraints exist. Although in the traditional sense they are primarily didactic in nature, demonstrations can often also employ aspects of constructivism, one of the major theories supporting the teaching and learning of science as inquiry. Brooks and Brooks (1999) define constructivist teachers as those that place high value on student questions, actively diagnose existing conceptions, and mediate the learning environment to allow for discoveries that facilitate the modification of existing knowledge. As with other instructional strategies, some types of demonstrations adhere to these principles and others clearly do not. Discrepant events are demonstrations that hold student attention in which the results are unexpected. Discrepant events serve a variety of purposes in successful inquiry-based learning environments. Some of their major functions are indicated below: Anticipatory Set Liem (1897) and others promote the use of discrepant events as an “invitation to inquiry.” These unexpected occurrences immediately generate student interest. Additionally, this engagement often leads to the formation of questions that may be used to drive future scientific inquiry. Diagnosing Conceptions The National Research Council (2000) emphasizes the importance of designing instruction around the preconceptions of learners. Discrepant events provide learners with the opportunity to challenge their own existing beliefs and provide teachers with the chance to gauge prior knowledge, which impacts future instruction. Learning Tool Both teacher-initiated and student-initiated inquiry can be planned around discrepant events. Although a variety of methods are feasible, one technique is particularly effective. It is the Predict-Observe-Explain (POE) method developed by White and Gunstone (1992): Predict Students anticipate the outcome of a discrepant event. Predictions are supported with explanations. Predictions may be formally recorded or collected and are often shared with the group. Observe Students witness the discrepant event. Observations are recorded. Explain Theories are generated to explain the results. Theories are discussed. Assessment Tool Assessments can be created around discrepant events. Since students are challenged to apply their knowledge/skills to a new situation, they must draw on higher-level thought processes. References Brooks, J., & Brooks, M. (1999). In search of understanding: The case for constructivist classrooms. Upper Saddle River, NJ: Merrill-Prentice Hall. Liem, T. (1987). Invitations to science inquiry. Chino Hills, CA: Science Inquiry Enterprises. Llewellyn, D. (2002). Inquire within: Implementing inquiry-based science standards. Thousand Oaks, CA: Corwin Press. Llewellyn, D. (2005). Teaching science through inquiry. Thousand Oaks, CA: Corwin Press. National Research Council. (2000). How people learn: Brain, mind, experience, and school. Washington, DC: National Academy Press. White, R. T., & Gunstone, R. F. (1992). Probing understanding. Great Britain: Falmer Press.

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