Chewing Gum and pH Level of the Mouth: A Model-based Inquiry Sequence to Promote Scientific Practices

Abstract

Television ads usually use scientific messages to highlight the benefits of the products they advertise. This is the case of a known brand of chewing gum that "helps to increase the oral pH after meals". From this starting point, we have developed a short sequence of activities (sensopills for 1.5h) with a Model-Based Inquiry teaching approach to engage students in scientific practices, and understand disciplinary core ideas and crosscutting concepts in order to promote critical consumers of information about science, as NRC recommend. We use a historical acid/base model (Lemery) to explain and predict oral pH phenomena. The sensopill "chewing gum" has been implemented with hundreds of secondary school students. Learning self-regulation results show that students recognized having learned the difference between dilution and neutralization and the concept of pH and their improvement at some scientific inquiry skills such as hypothesis formulation and data collection.

Changing How We Teach Acid-Base Chemistry

“…Instead of learning the models as the result of the scientific activity, it would be enough to focus on some specific big ideas (Harlen 2010) or key ideas (National Research Council 2012) that have the potential to explain a lot of different phenomena (Izquierdo-Aymerich and Aduriz-Bravo Fig. 7 Correspondence between the PACMAN model elements and chemical formulation (Jiménez-Liso et al 2018) 2003). Thus, a model-based teaching approach offers instructional strategies for improving conceptual learning in science education (Shen and Confrey 2007) and permits students go beyond the idea of models as reproduction, allowing them to reach the vision that the relationship between model, experiment, and reality is dynamic and evolutionary (Tasquier et al 2016).…”

Enseñanza del concepto de pH desde la perspectiva del pensamiento científico: una revisión sistemática exploratoria

“…En cuanto a los hechos, fue posible reconocer la importancia de la experimentación para el aprendizaje de conceptos químicos, esta consideración concuerda con otros autores como Blanchar, (2020), Urquizo y Sánchez (2019). Al abordar el concepto de pH, es común emplear experiencias caseras; sin embargo, es indispensable vincular el lenguaje oral, escrito, la interpretación de gráficos y dibujos, tal como lo señalan Jiménez et al (2018), para ampliar la posibilidad de su comprensión. De igual manera, es fundamental fortalecer los procesos de experimentación con la proposición de resultados y conclusiones.…”

“…Cabe destacar que en éste se puede evidenciar la generación de modelos mentales; sin embargo, se destaca la importancia de establecer modelos materiales a través de estrategias como laboratorios reales, uso de simuladores, ejercicios, así como clases magistrales. Uno de los estudios que más enfatiza en la creación de modelos fue realizado por Jiménez et al (2018), y propone la estrategia "mascar chicle y pH de la boca" con el fin de construir un modelo para explicar fenómenos ácido-base.…”

Why scientific practices are not included in Science lessons? What does it go unnoticed for teachers

“…To reach our main goal (Science with Sense, Sensors & Sensations, Jiménez-Liso, Avraamidou, Martínez-Chico & López-Gay, 2019), we develop micro-sequences (1.5 hours) called Sensopills (SP) though a Model-based Inquiry (MBI) approach. In these SPs (Jiménez-Liso et al, 2019;Jiménez-Liso, Martínez-Chico & Salmerón-Sánchez, 2018;Martínez-Chico, Evagorou & Jiménez-Liso, 2019;, in-service teachers are engaged in scientific questions in contexts that make sense for them and promote to explicit their conceptions when formulating and justifying their hypothesis; they look for evidence to test their responses by using sensors to collect and show in-screen real time data (the sensors mainly used are measuring devices connected to the computer with free software that allows real-time graphics to visualize the evolution of the variables); results are analysed to review their initial explanations or models and adapt them to the new information, and then communicate their conclusions. All the activities are developed in an environment of communication, reflection, share and dialogue, debating about the process and considering alternative explanations.…”

“…20-32 overall emotional climate of the in their class (Fried, Mansfield & Dobozy, 2015). Therefore, given the importance of training teachers to assist their students with their emotional regulation, and with the immediate intention of making our students to be aware of what they learn and feel when experiencing the activities, a self-regulation learning & emotions activity is included at the end of each SP (Jiménez-Liso et al, 2018;Jiménez-Liso, Giménez-Caminero, Martínez-Chico, Castillo-Hernández & López-Gay, 2019;Martínez-Chico et al, 2018.…”