directly the involved atomic energy levels, coupling in a 1:1 correspondence a single
emission line with a single energy level, rather than associating a single emission
with a quantum leap between a couple of levels (Rebello et al. 1998; Zollman et al.
2002). The problem of the conceptual link between spectral emissions and energy
levels presents several sub-facets: the fundamental level is not considered as a level
or it is involved in every transition (Korhasan and Wang 2016; Ivanjek 2012; Ivanjek
et al. 2015a, b). In introductive astronomy courses, where spectroscopy plays a
pivotal role, since absorption and emission of radiation represent the single tool to
infer information concerning the physical properties of celestial objects, difficulties
emerged in describing the process of luminous emission from atoms (Bardar et al.
2006). Among university students an idea emerges according to which the energy of
the radiation is linked to the intensity rather than to the colour, represented by
wavelength or frequency (Lee 2002). Students do not have a clear idea nor of the
quantum model for atoms, or of the quantum model for light, so they struggle to
predict the way they interact in emission and absorption processes (Savall-Alemany
et al. 2016). An evidence regarding the existence of spontaneous models concerning
the formation of discrete spectra and of their link with the quantized structure of
atoms emerges. Those models have to be overcome in order to reach a scientific view
of the topic (Gilbert et al. 1998a, b). Another plan in the conceptual knots is
represented by the role of the experimental setup in forming and detecting a
spectrum: among the most common conceptual difficulties, student believe that a
prism produces always a continuous spectrum and a diffraction grating produces
always a discrete spectrum independently by the role of the source (Ivanjek 2012;
Ivanjek et al. 2015a, b).
The learning path embeds explorative activities through which students correlate
macroscopic observations (spectral emissions) and microscopic interpretations (matter energy structure). This choice was guided by the observation that an educational
approach based on the spontaneous angles of attack to specific contents starting from
common sense ideas of students is a necessary condition in order to activate the
learning process (Viennot 2003).
19.3 The Educational Path
The educational path is built iteratively designing conceptual micro-steps in which
active learning strategies as inquiry-based learning and experimental explorations
produce the overcoming of the identified conceptual knots and the appropriation of
the founding disciplinary elements by means of Design-Based Research (DBR)
methods (DBR Collective 2003; Collins et al. 2004; Van der Akker et al. 2006;
Anderson and Shattuck 2012) according to which every conceptual micro-step is
designed, evaluated and redesigned iteratively on the basis of students’ responses.
The path has different steps (phases) described in detailed in the following.
The first strategic focus takes into account the classification of optical phenomena
in three big thematic areas: production, propagation and matter–light interaction
19 Research-Based Path Proposal on Optical Spectroscopy in Secondary School
241
emission line with a single energy level, rather than associating a single emission
with a quantum leap between a couple of levels (Rebello et al. 1998; Zollman et al.
2002). The problem of the conceptual link between spectral emissions and energy
levels presents several sub-facets: the fundamental level is not considered as a level
or it is involved in every transition (Korhasan and Wang 2016; Ivanjek 2012; Ivanjek
et al. 2015a, b). In introductive astronomy courses, where spectroscopy plays a
pivotal role, since absorption and emission of radiation represent the single tool to
infer information concerning the physical properties of celestial objects, difficulties
emerged in describing the process of luminous emission from atoms (Bardar et al.
2006). Among university students an idea emerges according to which the energy of
the radiation is linked to the intensity rather than to the colour, represented by
wavelength or frequency (Lee 2002). Students do not have a clear idea nor of the
quantum model for atoms, or of the quantum model for light, so they struggle to
predict the way they interact in emission and absorption processes (Savall-Alemany
et al. 2016). An evidence regarding the existence of spontaneous models concerning
the formation of discrete spectra and of their link with the quantized structure of
atoms emerges. Those models have to be overcome in order to reach a scientific view
of the topic (Gilbert et al. 1998a, b). Another plan in the conceptual knots is
represented by the role of the experimental setup in forming and detecting a
spectrum: among the most common conceptual difficulties, student believe that a
prism produces always a continuous spectrum and a diffraction grating produces
always a discrete spectrum independently by the role of the source (Ivanjek 2012;
Ivanjek et al. 2015a, b).
The learning path embeds explorative activities through which students correlate
macroscopic observations (spectral emissions) and microscopic interpretations (matter energy structure). This choice was guided by the observation that an educational
approach based on the spontaneous angles of attack to specific contents starting from
common sense ideas of students is a necessary condition in order to activate the
learning process (Viennot 2003).
19.3 The Educational Path
The educational path is built iteratively designing conceptual micro-steps in which
active learning strategies as inquiry-based learning and experimental explorations
produce the overcoming of the identified conceptual knots and the appropriation of
the founding disciplinary elements by means of Design-Based Research (DBR)
methods (DBR Collective 2003; Collins et al. 2004; Van der Akker et al. 2006;
Anderson and Shattuck 2012) according to which every conceptual micro-step is
designed, evaluated and redesigned iteratively on the basis of students’ responses.
The path has different steps (phases) described in detailed in the following.
The first strategic focus takes into account the classification of optical phenomena
in three big thematic areas: production, propagation and matter–light interaction
19 Research-Based Path Proposal on Optical Spectroscopy in Secondary School
241