Background
Given the growing interest in, and relevance of, integrated approaches to STEM (science, technology, engineering, and mathematics) education, there is an urgent desire to understand the ...challenges and obstacles to developing and implementing integrated STEM curricula and instruction. In this article, we present phase 1 of a two-phase needs assessment study to identify challenges and needs of promoting integrated approaches in STEM education. Utilizing a key informant approach, 22 K-12 teachers and four administrators selected as potential leaders in STEM education in an unidentified state on the East Coast of the USA were interviewed. Participants were asked to identify challenges and perceived supports to conduct integrated STEM education. Questions were open-ended in order to inform a larger, state-wide questionnaire study in phase 2 to be reported subsequently and were qualitatively coded.
Results
Several distinctive themes were identified as described by teacher participants when discussing challenges and obstacles of implementing integrated STEM education, as well as supports that would be most helpful in overcoming them. Participants also provided specific suggestions for teacher education needed to support integrated STEM education.
Conclusions
Preliminary findings suggest that many teachers are interested in integrated approaches to STEM, but do not believe they are well prepared to implement them. Teachers and administrators also suggest that adequate preparation in integrated STEM would entail a considerable rethinking and redesigning of pre-service courses and in-service workshops. Findings provide a starting point for better understanding teacher needs in integrated STEM and a springboard for further study.
Classroom learning environments are frequently assumed to exert their influence on learning indirectly, via student engagement. The present study examined the influence of environmental challenge and ...support on learning in high school classrooms, and the potential for student engagement to act as a mediator in this relationship. Data were collected in seven classrooms in six different subjects in several US high schools. The 104 students in these classes participated in the Experience Sampling Method (ESM) and reported records (N = 254) of engagement, learning, and related experiential variables. Measures of the learning environment were also rated from video footage. Variations in the learning environment observed and rated from video were linked to students’ real-time reactions to instruction synchronously. Results indicated that environmental support, but not environmental challenge, was significantly related with perceived learning. Multi-level path analyses revealed that the association between environmental supports and learning was mediated by student engagement. This mediating relationship held specifically for two components of environmental support: Motivational supports and supportive relationships. Implications are discussed for the benefit of practicing school psychologists, including strategies for facilitating motivational and relational support to enhance student engagement.
The present paper proposes a novel method of quantification of the variation in biofilm architecture, in correlation with the alteration of growth conditions that include variations of the substrate ...and conditioning layer. The polymeric biomaterials serving as substrates are widely used in implants and indwelling medical devices, while the plasma proteins serve as the conditioning layer. The present method uses descriptive statistics of field emission scanning electron microscopy (FESEM) images of biofilms obtained during a variety of growth conditions. We aim to explore here the texture and fractal analysis techniques, to identify the most discriminatory features which are capable of predicting the difference in biofilm growth conditions. We initially extract some statistical features of biofilm images on bare polymer surfaces, followed by those on the same substrates adsorbed with two different types of plasma proteins, viz., bovine serum albumin (BSA) and fibronectin (FN), for two different adsorption times. The present analysis has the potential to act as a futuristic technology for developing a computerized monitoring system in hospitals with automated image analysis and feature extraction, which may be used to predict the growth profile of an emerging biofilm on surgical implants or similar medical applications.
In this study, we conducted a model of teacher professional development (PD) on the alignment of middle and high school curricula and instruction to the Next Generation Science Standards (NGSSs), and ...evaluated the impact of the PD on teacher participants' development. The PD model included a 4-day summer academy emphasizing project-based learning (PBL) in the designing of NGSS-aligned curricula and instruction, as well as monthly follow-up Professional Learning Community meetings throughout the year providing numerous opportunities for teachers to develop and implement lesson plans, share results of lesson writing and implementation (successes and challenges), provide mutual feedback, and refine curricula and assessments. Following the summer academy, six female teachers were interviewed about their current conceptualizations of NGSS, the extent of curricular shifts made that are required by NGSS, their self-perceptions regarding their level of accomplishment in curriculum writing, and the benefits of the PD in reaching their goals related to NGSS. Interviews were supplemented with an analysis of lesson plans written while participating in the PD program. The interviewed teachers suggested that they had made important conceptual and pedagogical shifts required by NGSS as they participated in the PD, and also noted a variety of challenges as they made this shift. While all teachers were relative novices at NGSS curriculum writing before the PD, most of the teachers interviewed felt that they had achieved the status of an "accomplished novice" following the summer academy. An analysis of their written lessons suggested a great range in the extent to which teachers effectively applied their understanding of NGSS to write lessons aligned to NGSS. Interviewed teachers believed that the PD model was helpful to their development as science teachers, and all reported that there were no aspects of the PD that were not helpful. Even though most teachers obtained a basic understanding and conceptualization of NGSS and PBL, their application of this understanding in their curriculum writing varied. The present study may help to inform future efforts to support teachers to align curricula and instruction to NGSS through teacher PD.
Artificial intelligence research on creative design has led to Structure-Behavior-Function (SBF) models that emphasize functions as abstractions for organizing understanding of physical systems. ...Empirical studies on understanding complex systems suggest that novice understanding is shallow, typically focusing on their visible structures and showing minimal understanding of their functions and invisible causal behaviors. In this paper, we describe an interactive learning environment called ACT (for Aquarium Construction Toolkit) in which middle-school students construct SBF models of complex systems as a vehicle for gaining a deeper understanding of how such systems work. We report on the use of ACT in middle-school science classrooms for stimulating, scaffolding, and supporting SBF thinking about aquarium systems as examples of complex systems. We present preliminary data indicating that SBF thinking, facilitated in part by the ACT tool, leads to enhanced understanding of the behaviors and functions of aquaria.
Desiccation cracks form interesting patterns in natural and synthetic clays. Clay platelets, having a net negative surface charge in aqueous solution, are affected by an electric field. We report ...observation of cracks forming in a radial external electric field. The cracks start radially from whichever electrode is positive, whether it is the central or outer electrode. The same geometry without the field does not produce the characteristic radial pattern. The non-uniform nature of the field due to the radial arrangement is a crucial factor, we find that the uniform field produced in rectangular geometry does not show any distinctive feature. SEM images of the films show that the arrangement of the clay nano-platelets is quite different in samples dried with and without the external field. With no field, the particles are aligned linearly, presumably along defects on the substrate, but the electric field disrupts this alignment and produces a homogeneous disordered arrangement.
The purpose of this study was to investigate the linkage between the quality of the learning environment and the quality of students' experience in seven high school classrooms in six different ...subject areas. The quality of the learning environment was conceptualized in terms of environmental complexity, or the simultaneous presence of environmental challenge and environmental support. The students (N = 108) in each class participated in the Experience Sampling Method (ESM) measuring their engagement and related experiential variables. Concurrently, environmental complexity and its subdimensions were observed and rated from video with a new observational instrument, The Optimal Learning Environments – Observational Log and Assessment (OLE-OLA). Using two-level HLM regression models, ratings from the OLE-OLA were utilized to predict student engagement and experiential variables as measured by the ESM. Results showed that environmental complexity predicted student engagement and sense of classroom self-esteem. Implications for research, theory and practice are discussed.
•We investigate the linkage between the learning environment and student engagement.•High school students were observed and completed the Experience Sampling Method.•Environmental complexity accounted for variation in engagement and classroom self-esteem.•Engaging learning environments were characterized by combined challenges and supports.
Formation of extracellular polymeric substances (EPS) is a crucial step for bacterial biofilm growth. The dependence of EPS composition on growth substrate and conditioning of the latter is thus of ...primary importance. We present results of studies on the growth of biofilms of two different strains each, of the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae, on four polymers used commonly in indwelling medical devices polyethene, polypropylene, polycarbonate, and polytetrafluoroethyleneimmersed in bovine serum albumin (BSA) for 24 h. The polymer substrates are studied before and after immersing in BSA for 9 and 24 h, using contact angle measurement (CAM) and field emission scanning electron microscopy (FE-SEM) to extract, respectively, the “philicity” φ (defined as −cos θ, where θ is the contact angle of the liquid on the solid at a particular temperature and ambient pressure) and spatial Hirsch parameter H (defined from the relation F(r) ∼ r 2H , where F(r) is the mean squared density fluctuation at the sample surface). H = 0.5, <0.5, or >0.5 signifies no correlation, anticorrelation, and correlation, respectively. The substrates are seen to transform from large hydrophobicity to near amphiphilicity with the formation of a BSA conditioning surface layer, and the H-values distinguish the length scales of 100, 500, and 2000 nm, with the anticorrelation increasing with length scale. Biofilms of E. coli did not grow on bare PTFE and HDPE substrates. Biofilms grown on BSA-covered surfaces are studied with CAM, FE-SEM, Fourier transform infrared (FTIR), and surface-enhanced Raman spectroscopy (SERS). Both spectra and φ-values were independent of bacterial species but dependent on the polymer, while H-values show some bacterial variation. Thus, EPS composition and wetting properties of the corresponding bacterial biofilms seem to be decided by the interaction of the conditioning BSA layer with the specific polymer substrate.
In this paper, we share results from a classroom intervention that used a conceptual representation to support reasoning about ecosystems. Engaging students in modeling allows them to make their ...ideas visible while being malleable and available for discussion, which enables students to make meaning out of systems. Further, the Components-Mechanisms-Phenomena (CMP) conceptual representation was designed to enable students to construct coherent mental models. Following our intervention, students deepened their understanding of ecosystem dynamics when compared to students who engaged in traditional instruction without use of the CMP conceptual representation. We discuss our results in terms of data that helped guide the design of the intervention and we describe a theoretical perspective that can be used to guide future instruction.
Computer-supported collaborative learning environments provide opportunities for students to collaborate in inquiry-based practices to solve authentic problems, using technological tools as a ...resource. However, we have limited understanding of the quality of engagement fostered in these contexts, in part due to the narrowness of engagement measures. To help judge the quality of engagement, we extend existing engagement frameworks, which have studied this construct as a stable and decontextualized individual difference. We conceptualize engagement as multi-faceted (including behavioral, social, cognitive and conceptual-to-consequential forms), dynamic, contextualized and collective. Using our newly developed observational measure, we examine the variation of engagement quality for ten groups. Subsequently, we differentiate low and high quality collaborative engagement through a close qualitative analysis of two groups. Here, we explore the interrelationships among engagement facets and how these relations unfolded over the course of group activity during a lesson. Our results suggest that the quality of behavioral and social engagement differentiated groups demonstrating low quality engagement, but cognitive and conceptual-to-consequential forms are required for explaining high quality engagement. Examination of interrelations indicate that behavioral and social engagement fostered high quality cognitive engagement, which then facilitated consequential engagement. Here, engagement is evidenced as highly interrelated and mutually influencing interactions among all four engagement facets. These findings indicate the benefits of studying engagement as a multi-faceted phenomenon and extending existing conceptions to include consequential engagement, with implications for designing technologies that scaffold high quality cognitive and conceptual-to-consequential engagement in a computer-supported collaborative learning environment.
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