Following Darwin's footsteps: Evaluating the impact of an activity designed for elementary school students to link historically important evolution key concepts on their understanding of natural selection

While several researchers have suggested that evolution should be explored from the initial years of schooling, little information is available on effective resources to enhance elementary school students' level of understanding of evolution by natural selection (LUENS). For the present study, we designed, implemented and evaluated an educational activity planned for fourth graders to explore concepts and conceptual fields that were historically important for the discovery of natural selection. Observation field notes and students' productions were used to analyse how the students explored the proposed activity. Additionally, an evaluation framework consisting of a test, the evaluation criteria and the scoring process was applied in two fourth-grade classes to estimate elementary school students' LUENS before and after engaging in the activity. Our results suggest that our activity allowed students to effectively link all of the key concepts in the classroom and produced a significant increase in their LUENS. These results indicate that our activity had a positive impact on students' understanding of natural selection. They also reveal that additional activities and minor fine-tuning of the present activity are required to further support students' learning about the concept of differential reproduction. We also observed a low level of teleological predictions for both pre- and post-tests. --For all the items except LUENS, a value of 1,00 means present and a value of 0,00 means absent from that students' answers. Missing data (items for which absence or presence could not be ensured, there was no agreement between the two coders, or, in case of LUENS, could not be estimated) is represented by "?". For LUENS, the presented values correspond to the sum of the scores attributed for each rubric item identified in that answer, regarding both predictions and corresponding justifications. A score of 1 was attributed to the items "fittest", "resource availability" and "differential survival", a score of 2 was attributed to "differential reproduction" and a score of zero was attributed to all other items. Funding provided by: Fundação para a Ciência e a TecnologiaCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100001871Award Number: UID/CED/00194/2019Funding provided by: European Research CouncilCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100000781Award Number: COMPCON, GA 725419Funding provided by: Ministerio de Ciência, Innovación y UniversidadesCrossref Funder Registry ID: http://dx.doi.org/10.13039/100014440Award Number: Project PGC2018-096581-B-C22Funding provided by: Fundação para a Ciência e a TecnologiaCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100001871Award Number: I.P.2020.05634.BDFunding provided by: COST Action*Crossref Funder Registry ID: Award Number: CA17127Funding provided by: COST ActionCrossref Funder Registry ID: Award Number: CA17127This dataset is the result of the evaluation of elementary school students' answers to the evaluation instrument used as pre and post test in paper. The evaluation instrument can be found in the appendix of the manuscript. Shortly, the evaluation instrument asked students to think forward in time and predict the outcome of a biological scenario, and describe how a butterfly population would look in 100 years. The test was read aloud to the class and students were asked to write a justified prediction and draw it. To evaluate students' answers, we used criteria developed by other authors (Kelemen et al., 2014; Sá-Pinto et al., 2017a) in the context of the aforementioned framework. These were complemented with the inclusion of another criterion that targets whether students' predictions integrate information about the selective pressure: resource availability. These criteria formed the items of our rubric. The complete definitions of each rubric item are provided in Table A2 in Appendix . These rubric items allowed us to classify answers according to the student's type of prediction (i.e., fixist, fittest or equilibrium) and the justification provided (i.e., developmental, teleological, resource availability, differential survival or differential reproduction). The level of understanding of evolution by natural selection (LUENS) revealed by each answer was determined by the sum of the scores attributed for each rubric item identified in that answer, regarding both predictions and corresponding justifications. A score of 1 was attributed to the items "fittest", "resource availability" and "differential survival", a score of 2 was attributed to "differential reproduction" and a score of zero was attributed to all other items. Two independent researchers—one evolutionary biologist with a background in science education and one elementary school teacher evaluated all the students' answers. Answers not equally rated by the two researchers were discussed and, if a consensus could not be reached, these were removed from the analysis