Association Between Experienced Teachers’ NOS Implementation and Reform-Based Practices

Abstract

The assertion that general reform-based science teaching practices (GRBSTPs) can facilitate nature of science (NOS) instruction has been mentioned in the literature, but rigorous and transparent empirical substantiation for this claim has not been made. This investigation empirically demonstrates an association between thirteen experienced teachers’ NOS implementation practices and their GRBSTPs. While effectively implementing GRBSTPs does not ensure the NOS will be taught, the findings show that these practices are associated with high levels of NOS instruction. In this study, teachers who implemented higher levels of reform-based practices were also observed to enact more instances of planned and spontaneous effective NOS instruction. Furthermore, these teachers were more likely to recognize and capitalize on NOS teaching opportunities when they unexpectedly arose in the context of their GRBSTPs. Just as NOS understanding must be assessed when determining factors associated with teachers’ NOS implementation, teachers’ GRBSTPs should also be empirically and transparently established to ensure they do not mask or confound other factors associated with NOS implementation.

Appendices

Appendix 1

Table 5 Nature of Science Classroom Observation and Artifact Protocol (NOS-COP)

Appendix 2

Notable features of participants’ lessons and associated LSC-COP capsule (Horizon Research, Inc. 2006) and NOS-COP ratings.

LSC-COP Capsule Rating Level 1: Ineffective Science Instruction (Score: 1)

Example Lesson Mary, Observation 3. Mary required students to memorize technical names and classifications of protists (e.g., tetrahymena, paramecium) through lecture. She led the class in playing “hangman” during the last 20 min of a 45-min class period. Observer noted: (a) developmentally inappropriate, highly technical content, (b) teacher-centered interaction pattern (lecture with few questions, students often guessing, teacher providing desired responses) used to lecture about protists’ names, (c) students not required to demonstrate an understanding of a central science idea, d) game is trivial and irrelevant to science. NOS-COP Rating: 1—Explicit NOS instruction is absent.

LSC-COP Capsule Rating Level 2: Elements of Effective Instruction (Score: 2)

Example Lesson Philip, Observation 1. Philip conducted a demonstration about the amount of available freshwater on earth. He lectured about water conservation and pollution through a digital presentation. He required students to complete “Fun Facts About Water” true/false worksheet. Observer noted: (a) small amounts of inquiry infused in demonstration, but poor interaction patterns (e.g., yes/no questions with poor wait time) encouraged random guessing by students, (b) lecture about content was developmentally appropriate, but required no student interaction, (c) assessment of students’ thoughts limited to responses on true/false worksheet. NOS-COP Rating: 1.2—Explicit NOS instruction is absent. Phillip vaguely made statements, while lecturing about water quality, about how lawmakers can influence water quality regulations. However, he made no connection to how lawmakers can influence scientific research on water quality.

LSC-COP Capsule Rating Level 3: Beginnings of Effective Instruction (3-low Score: 3) (3-solid Score: 4) (3-high Score: 5)

Example Lesson (3-low) Maddy, Observation 3. Maddy reviewed the comparisons of prokaryotes and eukaryotes and cell structure. She reminded students that science can only study natural world phenomena. She showed several videos about three competing science ideas of how life began on earth. She discussed the salient ideas portrayed in the videos. Observer noted: (a) content review somewhat trivial, fact based, and developmentally inappropriate; (b) statements about how science works had no reflective questions; (c) videos were engaging, developmentally appropriate, and provided a context that would encourage students to understand science content about how life began on earth; (d) Maddy asked students questions about the videos presented in class. However, her students only superficially reflected upon the identified science ideas because of her ineffective interaction patterns (e.g., short wait time, yes/no questions). NOS-COP Rating: 2—The videos presented three competing “theories” about how life began. Maddy’s statements about how science is limited to understanding natural phenomena were erroneous, superficial, and decontextualized (e.g., science can only “prove” how natural phenomena occur through evidence, with no follow-up questions or links to actual science content). Implicit and partially accurate NOS ideas presented in video (e.g., scientists discover ideas akin to discovering a lost item, competing scientific theories can explain the same natural phenomena). In relation to class videos, Maddy insinuates scientific theories can be supported by varying levels of evidence, but can also be “just an idea.” Students were not required to reflect upon NOS ideas (e.g., the nature of theories, tentativeness of science, creativity) present in the videos.

Example Lesson (3-solid) Mary, Observation 1. Mary conducted an inquiry discussion where students speculated the causes of moon phases while looking at moon phase illustrations. Students completed a teacher-led inquiry activity using globes and flashlights as models to test their predictions about how moon phases occur. Students’ ideas about how moon phases occur were posted on the board and discussed in the context of established science content about moon phases. Observer noted: (a) When eliciting students’ predictions about moon phase causes, Mary’s interaction patterns were of mixed effectiveness (e.g., yes/no questions interspersed with open-ended thought-provoking questions); (b) The inquiry activity helped students generate ideas about how moon phases occur, but Mary’s classroom management struggles and interactions with small groups caused students to generate these ideas superficially; (c) Post-activity discussion was rushed and contained rough transitions due to ineffective classroom interactions and management. This caused students to become confused when Mary tried to post students’ ideas on the board, and then link those ideas to established and developmentally appropriate science content about moon phases. NOS-COP Rating: 1—Explicit NOS instruction is absent.

Example Lesson (3-high) Carey, Observation 1. Students began inquiry salsa canning laboratory activity while Carey asked students to speculate about implementing certain procedures (e.g., boiling the salsa, washing hands, and ensuring a vacuum). During the activity, Carey asked students where they have seen spoiled food at home, speculate on the causes of food spoilage, and directed them to spoil food at home in a jar and record the process. Carey read about Redi’s experiment. Carey punctuated the reading with discussion of relevant science ideas with students. Students completed the canning activity and were directed to make 21 days of observations of improperly sealed jars of salsa. Carey discussed with students the role of prior knowledge when making conclusions, Redi’s studies, and advancements in hygiene. Observer noted: (a) concrete canning activity and Carey’s effective questions caused students to speculate about causes of food spoilage—creating a scaffolding point for later teaching about Redi’s studies and NOS; (b) Carey used students’ experiences with spoiled foods to scaffold into the story and discussion about Redi’s studies, bacterial growth, and the NOS; (c) Redi’s story was meaningful and developmentally appropriate. During the reading, Carey asked students questions about science and NOS ideas (e.g., how people’s prior knowledge influenced their ideas about spontaneous generation) and also discussed these topics after students completed the canning activity; (d) Carey’s interaction pattern was of mixed effectiveness (e.g., first asking open-ended questions and then providing students the desired answer, utilizing lecture with difficult science and NOS topics). NOS-COP Rating: 3.2—While discussing Redi and students’ ideas about how they would know what causes food spoilage, Carey described how people in the 1600s lacked the prior knowledge necessary to make alternative inferences besides spontaneous generation when seeing maggots on meat. Carey also attends the students to how science is tentative and can change based on evidence. However, Carey neglected to have her students deeply reflect upon these identified NOS themes. Carey links the highly contextualized NOS story about Redi to the moderately contextualized canning laboratory by first asking the students: if they saw maggots in the jars, how would they know what happened? She then leads the students to understand they had made an inference based on prior knowledge. However, Carey does not extensively address the nature of scientific observations and inferences.

LSC-COP Capsule Rating Level 4: Accomplished, Effective Instruction (Score: 6)

Example Lesson Sharon, Observation 2. Students were asked to consider the previous day’s activity where they recorded when particular steps (e.g., data analysis, predictions) occur (i.e., at the beginning, middle, end) during scientific investigations. Students discuss in groups Sharon’s question about why they should not claim each step occurs at a fixed time during scientific investigations. Students completed an activity investigating the relationship between scales of measurement (e.g., cm and m) while again noting the times they completed (or did not complete) particular investigation steps (e.g., data analysis, predictions). Sharon interacts with small groups about their ordering of their investigative steps. Using the context of relationships, Sharon and students discuss how “everyday” informal language and scientific language differ. Observer noted: (a) Sharon used highly effective scaffolding questions and wait time and drew upon students’ prior classroom experiences; (b) students were required to document ideas on whiteboards during group discussions; (c) Sharon circulated around the room to assess students’ understanding about how science works, and encouraged further understanding through interactive discourse; (d) the activity was developmentally appropriate and provided context for students to discuss how science works; (e) the activity would have been more effective by focusing on the development of a science idea, rather than investigating measurement standards relationships; (f) accurate ideas about science and scientific language were promoted through discussion about classroom experiences. NOS-COP Rating: 3.6—Students were required to explicitly reflect through decontextualized and moderately contextualized inquiry experiences how science does not follow a fixed scientific method. Students were required to contemplate and explain how classroom activities portrayed how science works. Students were asked to explain how words can possess a scientific and non-scientific meaning. Sharon, at times, struggled to use scaffolding questions directly related to the NOS. In these instances, Sharon either abandoned these questions or reworded them to yes/no or short-answer questions, limiting the level of reflection required of students.

LSC-COP Capsule Rating Level 5: Exemplary Instruction (Score: 7)

Example Lesson Luke, Observation 2. Luke modeled and interactively discussed with students ways to group objects (e.g., markers, scissors) through dichotomous schemes. Luke facilitated a discussion with students to develop a classification scheme for clothing (e.g., shirts, long-sleeved shirts, short-sleeved shirts). Students completed, with Luke’s assistance, an inquiry activity where they invent and use classification schemes to group rocks. Luke and the students interactively discussed biological classification and how this science idea was developed. Observer noted: (a) Luke used concrete decontextualized classification examples and effective scaffolding questions to create a context for later teaching about biological classification and the NOS; (b) while students invented rock classification schemes, Luke circulated the room and formatively assessed, through effective questioning, the students’ understanding of classification schemes and the logic behind classification in science; (c) through Luke’s effective questions and drawing upon students’ prior experiences (e.g., discussion about classification and inquiry rock classification activity), the students gained an understanding of developmentally appropriate ideas about biological classification. NOS-COP Rating: 4.3—Luke asked students about the logic behind classifying objects and how classification schemes help scientists understand the natural world, Luke directed the students to consider and reflect upon the extent that classification schemes provide a predictive framework for scientists to understand genetic relationships, are tentative, and have changed through scientists’ better understanding of genetic relationships between species. Luke then asked the students to reflect how this example relates to other instances in science. Luke facilitated an unplanned discussion where he drew upon previous decontextualized NOS classroom experiences (e.g., discussion about the tentative NOS and black-box investigations) that helped students reflect upon and understand the inventive NOS in the context of biological classification.