A core component of scientific inquiry is the ability to evaluate evidence generated from controlled experiments and then to relate that evidence to a hypothesis or theory. The control-of-variables strategy (CVS) is foundational for school science and scientific literacy, but it does not routinely develop without practice or instruction. This meta-analysis summarizes the findings from 72 intervention studies at least partly designed to increase students' CVS skills. By using the method of robust meta-regression for dealing with multiple effect sizes from single studies, and by excluding outliers, we estimated a mean effect size of g = 0.61 (95% CI = 0.53–0.69). Our moderator analyses focused on design features, student characteristics, instruction characteristics, and assessment features. Only two instruction characteristics – the use of cognitive conflict and the use of demonstrations – were significantly related to student achievement. Furthermore, the format of the assessment instrument was identified as a major source of variability between study outcomes. Implications for teaching and learning science process skills and future research are discussed

Mitigating and adapting to climate change requires foundational changes in societies, politics, and economies. Greater effectiveness has been attributed to actions in the public sphere than to the actions of individuals. However, little is known about how climate literacy programs address the political aspects of mitigation and adaptation. The aim of this systematic literature review is to fill this gap and analyze how public-sphere actions on mitigation and adaptation are discussed in climate literacy programs in schools. Based on database searches following PRISMA guidelines we identified 75 empirical studies that met our inclusion criteria. We found that central aspects of climate policy such as the 1.5-degree limit, the IPCC reports, or climate justice are rarely addressed. Whilst responsibility for emissions is attributed to the public sphere, the debate about mitigation usually focuses on the private sphere. Climate change education does not, therefore, correspond to the climate research discourse. We show that effective mitigation and adaptation are based on public-sphere actions and thus conclude that effective climate education should discuss those public actions if it is to be effective. Hence, we propose that climate education should incorporate political literacy to educate climate-literate citizens.

Many science curricula and standards emphasise that students should learn both scientific knowledge and the skills associated with the construction of this knowledge. One way to achieve this goal is to use inquiry-learning activities that embed the use of science process skills. We investigated the influence of scientific reasoning skills (i.e. conceptual and procedural knowledge of the control-of-variables strategy) on students’ conceptual learning gains in physics during an inquiry-learning activity. Eighth graders (n = 189) answered research questions about variables that influence the force of electromagnets and the brightness of light bulbs by designing, running, and interpreting experiments. We measured knowledge of electricity and electromagnets, scientific reasoning skills, and cognitive skills (analogical reasoning and reading ability). Using structural equation modelling we found no direct effects of cognitive skills on students’ content knowledge learning gains; however, there were direct effects of scientific reasoning skills on content knowledge learning gains. Our results show that cognitive skills are not sufficient; students require specific scientific reasoning skills to learn science content from inquiry activities. Furthermore, our findings illustrate that what students learn during guided inquiry activities becomes visible when we examine both the skills used during inquiry learning and the process of knowledge construction. The implications of these findings for science teaching and research are discussed.

The so-called control-of-variables strategy (CVS) incorporates the important scientific reasoning skills of designing controlled experiments and interpreting experimental outcomes. As CVS is a prominent component of science standards appropriate assessment instruments are required to measure these scientific reasoning skills and to evaluate the impact of instruction on CVS development. A detailed review of existing CVS instruments suggests that they utilize different, and only a few of the four, critical CVS sub-skills in the item development. This study presents a new CVS assessment instrument (CVS Inventory, CVSI) and investigates the validity of student measures derived from this instrument utilizing Rasch analyses. The results indicate that the CVSI produces reliable and valid student measures with regard to CVS. Furthermore, the results show that the item difficulty depends on the CVS sub-skills utilized in item development, but not on the item content. Accordingly, previous instruments that are restricted to a few CVS sub-skills tend to over- or underestimate students’ CVS skills. In addition, these results indicate that students are able to use CVS as a domain general strategy in multiple content areas. Consequences for science instruction and assessment are discussed.