Inquiry Based Learning Spaces For Stem Education

INQUIRY-BASED LEARNING SPACES FOR STEM EDUCATION

INTRODUCTION

Electricity production is a fundamental cause of industrial air pollution on Earth. The extensive use of coal and other non-renewable resources for providing electricity has taken a severe toll on Earth’s environment.

Fortunately, renewable energy resources can be used to produce electricity, causing a smaller impact on our planet. These resources have the advantage of being abundant, free and available in some quantity nearly everywhere and, most importantly, they do not harm the environment in any way [1].

Alternate-energy lessons should be adapted by all high schools, especially by those focused on international priorities and strategies in the domain of energy efficiency (e.g. in buildings) [2]. Therefore, new and improved teaching methods should be set up so that students get a better understanding of renewable energy sources and their vital role in sustainable development and environment protection and raising awareness about the long-term benefits of alternate energy resources [3].

An inquiry approach to education, involving teachers as the main stakeholders, and ensuring the commitment of other stakeholders like science laboratories is crucial for favorable development [4, 5]. Taking these recommendations into account, the Go-Lab project’s goals are: encouraging young students to engage in science topics, to acquire scientific inquiry skills, and to have the benefit of studying science in a motivating setting by undertaking active, guided, experimentation, carried out with more basic and top-level scientific facilities. Making science labs available online for this purpose could be one of the largest revolutions yet to come in our educational system [6]. It is very important to involve teachers in this process in order to ensure a smooth embedment in the curriculum and daily lessons of inquiry-based learning [7]. It provides teachers with a concrete way to implement online labs in pedagogically structured learning spaces and provides students with instructional guidance and opportunities for social interaction alongside the online laboratories.

Inquiry Learning Space

Two main requirements must be fulfilled for a learning material to be considered an open educational resources (OERs): free access to knowledge, and the capacity to reuse or adapt materials. A wide range of learning materials fit this criteria. In the area of STEM (Science, Technology, Engineering and Mathematics), Open Discovery Space, Open Science Resources, PhET, and weSPOT can all be used to create learning resources.

This paper shows how ILSs and other rich educational resources may be offered as OERs. Two unrelated platforms, Graasp [8] which is an inquiry learning space factory and Golabz [9] which is an inquiry learning space repository, enable teachers to create, share, discover, or adapt learning resources. Go-Lab enables inquiry-based learning, promoting acquisition of deep domain knowledge and inquiry skills, and directing students to scientific careers.

Compared to the traditional ILS setting, in inquiry-based learning the resources are not assembled by self-teaching students, but rather by teachers, who have the a great need for contextualization and repurposing as well. This project is an ongoing initiative aimed at promoting inquiry learning with online laboratories for STEM education at school [10].

For example, users can perform experiments online, obtaining results based on their choices of the panel's tilt angle, distance between solar panel and light source and can observe the changes of the characteristic curve. Additionally, the user can compare the theoretical curve with the experimental one for more accurate results.

The whole procedure is followed by a comprehensive discussion, during which participants share their inquiry process and results with the rest, presenting and communicating their findings and outcomes and reflecting upon each other’s performances, leading to substantial academic development regarding the topic area.

Fig. 1 – Orientation phase (http://graasp.eu/spaces/553fee85bdb6c43fd9dea662 )

Fig. 2 – The preview page of an ILS (http://www.golabz.eu/spaces/remote-photovoltaic-lab )

In order to find the most interesting ILSs, the Lab Repository provides several social media mechanisms, such as rating, commenting and sharing. The future addition of social badges [11] has been taken into consideration. Through them, other teachers and Go-Lab experts would be able to highlight the best labs, apps and ILS. Using these social validation mechanisms, the shared resources can be curated by the ‘wisdom of the crowd’.

PHOTOVOLTAICS

Solar cell is a device, which in incidence of light radiation, acts as an electrical generator, converting solar energy into electricity. The bases of this process has three basic phenomena [12]. Firstly, incident light is absorbed by solar cell which generate the non-equilibrium electron-hole pairs, then photo-generated charge carriers separated in the internal electric field. Finally, photo-generated charge carriers are collected in the in the external circuit as shown in Fig. 3:

Fig. 3 – PN junction formation [13]

In a solar cell, a p-n junction consists in which the core transition from n-type to p-type conductivity takes place [14, 15]. It is known that the n-type region has a high electron concentration and the p-type a high hole concentration, electrons diffuse from the n-type side to the p-type side.

If the voltage V is applied on p-n junction, in forward bias conditions, the potential barrier drop with the value qV, and the flux of majority charge carriers through junction, rapidly increases quickly, while the flux of minority charge carriers remains unchanged. The intensity of electric current determined by flux of majority charge carrier increases exponentially with the applied voltage, as shown in equation-:

(1)

When there is reverse bias conditions, the current rest about constant having the same intensity:

(2)

So the current-voltage (I-V) characteristic in the dark is given by:

(3)

This important relation is very well known as Shockley equation for an ideally p-n junction. Generally for a real p-n junction diode the dark current–voltage characteristics is described by this modified Shockley equation [16–17]:

(4)

where: I0, n, Rs and Rsh are the reverse saturation current, diode quality factor, series and shunt resistance of the cell, respectively, and q is the electronic charge.

There are different types of solar cells, however the ones based on silicon semiconductor diodes are the widely used in the large scale application, because of their high power conversion efficiency, more than 27%.

The power produced by a solar cell by a load resistor Rs can be calculated using the expression:

(5)

Taking into account the definitions of Voc and Isc, there is a value of the load resistor, for which the power transferred from the cell rich its maximum value. The "fill factor", commonly known by its abbreviation "FF", is a parameter which, in conjunction with Voc and Isc, determines the maximum power from a solar cell. Using the coordinates of this point the Fill Factor, defined by:

(6)

The efficiency of a solar cell is determined as the fraction of incident power which is converted to electricity and is defined as:

(7)

Where Pin is the light power density incident on the cell.

METHODS AND RESULTS

The project’s aim was to develop a remote solar cell experiment that enables distance learning students to investigate the effects of irradiance and temperature on electrical characteristics of solar cell using the IV curve, proving its potential for teaching students around the world.

In this study we presented IV characteristics of silicon solar cell with different light intensities using remote control solar cell experiment. Wolfram Mathematica code used to draw I-V and P-V graphs.

Vernier light sensor was used to measure intensity at different distances. Under the steady-state conditions, the I–V and power-voltage (P-V) characteristics have been obtained for solar pane with light intensity as shown in figure 4 and 5.

Table-1

Fig. 4 – IV curve of solar panel

Fig. 5 – Power-voltage curve of solar panel

As mentioned in the introduction, the Go-Lab Project focuses on supporting STEM education at school. One pilot activity has been developed by four school teachers. They have found that structuring the learning scenarios according to the ILS phases was challenging at the beginning, but gradually became simpler and more straightforward. As soon as teachers mastered the usage of Graasp, they started to be creative when integrating resources, apps and labs.

The second activity involved a group of students from 10th and 11th grade. The students’ feedback showed that they were incredibly pleased with attending this type of lessons, with the help of interactive content like videos, links, pictures and apps. Besides, the students were particularly satisfied with the lack of time constraints. Those who were not able to finish their assignments during the session could complete them at home, without affecting their grades for in-class assignments.

CONCLUSION

The concept of inquiry-based learning places being created, shared, and reused as Open Education Resources has been developed for STEM lessons in this paper. The proposed approaches and platforms enable straightforward use of the complete design and implementation of personalized resources supporting high-level personal and inquiry learning activities for both teachers and their students.

Students have to travel from one country to another to improve their knowledge, which can be very tiring and expensive. This paper proposes a valid solution to this problem: distance learners can study from home with ILS. Online labs can improve their practical knowledge and allow them to repeat the experiment at a suitable time, this being often impossible in a physical experiment.

The facilities that Go-Lab offers for creating and sharing complete learning environments through online labs is one of the major selling points, attracting lab-owners and teachers. Our experience with teachers up until now has been remarkably positive. From a technical point of view, the way the Go-Lab system set up does not pose any major obstacles; teachers can very quickly create their first ILSs. This means that the main challenge will lie in informing teachers on how to create well-designed, inquiry-based environments. Separating ourselves from strictly guided procedural approaches when learning in labs or practical sessions will require a major shift in thinking. We hope that providing teachers with good examples of ILSs and default ILSs will be a source of inspiration.

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