Light

In the Light SAILS inquiry and assessment unit, students examine the physical properties of light and its interaction with materials in a predominately qualitative fashion. A series of eight activities are described that aim to develop students' understanding of the concept of light and its characteristics. Students are facilitated to identify that sources of light have specific physical characteristics and these can determine the properties of light, such as its colour and intensity. Students can investigate the interaction of light with matter and explore phenomena such as reflection and refraction. The unit activities are presented as a guided inquiry-based approach and an individual student worksheet is provided for each activity.

This unit presents several opportunities for the assessment of different inquiry skills, and in particular, planning investigations, developing hypotheses, forming coherent arguments and working collaboratively. In addition, students can develop their scientific reasoning and scientific literacy skills. The assessment methods used across the activities of the unit include teacher observation, classroom dialogue, student worksheets and self-assessment.

This unit was trialled by teachers in three countries – Ireland, Greece and Germany, as described in the four case studies (students aged 12-18; mixed ability and gender). The teaching approach adopted was guided inquiry in all cases. The assessment of forming coherent arguments is described in all of the case studies, and in addition planning investigations, developing hypotheses and working collaboratively were assessed in some classes. Two of the teachers assessed scientific literacy (explaining concepts scientifically) and one teacher assessed the student's scientific reasoning (making reasoned decisions)

Unit booklet

Key content / concepts

Sources of light
Representation of how light travels
Shadows, and what determines the size of the shadow on a screen
Composition of white light, primary colours and the effect of filters
Reflection and image formation in plane mirrors
Refraction and image formation in lenses

Level

Lower
Upper

Inquiry skills and competencies assessed

Planning investigations
Developing hypotheses
Forming coherent arguments
Working collaboratively
Scientific reasoning
Scientific literacy

Assessment methods

Classroom dialogue
Teacher observation
Self-assessment
Worksheets

The teaching and learning activities described in the Light SAILS inquiry and assessment unit were developed by the FP7 ESTABLISH project, http://www.establish-fp7.eu/resources/units/light and adapted for use in the SAILS project. The unit develops in eight parts (activities A-H), in which students are introduced to a range of concepts and ideas, such as classification of objects by optical characteristics, physical properties of light (colour, intensity), shadows and light that cannot be seen by the naked eye. This information can be built upon to address the concept of light as a wave and representation of light waves as rays. Students are encouraged to consider mirrors and lenses and the way light acts (reflection and refraction). Finally, students examine white light, looking at combination of colours, primary colours, filters and lenses.

There are opportunities throughout this unit for the development and assessment of inquiry skills. Evidence of both content knowledge and skill development can be collected in the form of dedicated student worksheets for each activity, through teacher observation and self-assessment. While some assessment tools (3-point rubrics) are described within this unit, teachers are free to devise and implement their own assessment instruments. Suggested skills to be assessed during implementation of this unit include developing hypotheses, planning investigations, and scientific literacy. In particular, criteria for making judgements on six of the main skills encountered in this unit are outlined.

Below you can find the full inquiry and assessment unit for download, as well as an archive with classroom materials, including student worksheets and assessment tools for teachers to be used during the activities if available.

Unit booklet Classroom materials

Activity A: What are sources of light?

Concept focus	Sources of light
Inquiry skills focus	Forming coherent arguments
Scientific reasoning	Identifying light sources
Scientific literacy	Reviewing prior knowledge Understanding the properties of light
Assessment methods	Classroom dialogue Worksheets

Students are introduced to sources of light and differentiating between objects that are sources of light and those that are not. The learning aims identified are (1) triggering the students’ interest in light, (2) differentiating between objects that are sources of light and those that are not, (3) understanding that sources of light have different properties, and (4) understanding that light may not necessarily be visible to the human eye.

Activity B: How does light travel?

Concept focus	Light is a wave
Inquiry skills focus	Forming coherent arguments
Scientific literacy	understand that light is a wave, that light reflects from walls, and that how light can be modelled using rays
Assessment methods	Classroom dialogue Worksheets

The aim of this exercise is to establish in the students’ minds that light is a wave, that light exists in the space around them, that light reflects from the wall, and that light can be modelled using rays.

Activity C: Understanding shadows

Concept focus	Shadows are the absence of light
Inquiry skills focus	Planning investigations Forming coherent arguments
Scientific literacy	Understanding shadows and what determines the size of a shadow on a screen
Assessment methods	Classroom dialogue Worksheets

Students are encouraged to consider the formation of shadows. They investigate parameters that affect formation of shadows, and develop an understanding of shadows and what determines their size on a screen. Students are challenged to interpret their observations and use this to infer information about the properties of light.

Activity D: Exploring white light and filters

Concept focus	White light as a mixture of colours Use of filters
Inquiry skills focus	Developing hypotheses Forming coherent arguments
Scientific literacy	Understanding how concepts relate to real world context
Assessment methods	Classroom dialogue Worksheets

This activity explores the concept that white light is composed of many different colours. To demonstrate this phenomenon, students investigate the effects of filters. They observe that the filter only allow some colours through, thus they can begin to understand that each colour is a component of white light. They are encouraged to consider the everyday experience of a rainbow forming, and relate this to the observations from their laboratory observations. This seeks to develop their scientific literacy.

Activity E: Exploring primary colours

Concept focus	White light as a mixture of colours – primary colours
Inquiry skills focus	Forming coherent arguments
Scientific literacy	Explain phenomena scientifically Identify the real-world context of concepts
Assessment methods	Classroom dialogue Worksheets

This activity builds on the concept of white light as a mixture of colours. Students will be familiar with the seven colours observed when light is passed through a prism, or when a rainbow is formed. This activity seeks to explore primary colours, leading to an understanding that mixing red, green and blue light can produce white light. The concept of primary colours can be demonstrated effectively through examining pixels of a screen (phone or computer) using a magnifying glass.

Activity F: Exploring plane mirrors

Concept focus	Light rays travel in straight lines Plane mirrors reflect light Angle of incidence equals the angle of reflection
Inquiry skills focus	Developing hypotheses Forming coherent arguments
Scientific literacy	Understanding the real world context of this topic
Assessment methods	Classroom dialogue Worksheets

In this activity, students are asked to consider reflection. They explore the use of plane mirrors, allowing them to consolidate their understanding that plane mirrors reflect light. Building upon this concept, they identify the relationship that “the angle of incidence equals the angle of reflection.”

Activity G: Exploring refraction

Concept focus	Understanding refraction Understanding that light can be reflected from and transmitted through an interface
Inquiry skills focus	Forming coherent arguments
Scientific literacy	Explain refraction scientifically
Assessment methods	Classroom dialogue Worksheets

In this activity students are introduced to a further property of light, that of refraction. Through experimentation they can explore refraction, and observe what occurs when light travels from one medium to another.

Activity H: Exploring white light and filters

Concept focus	Exploring lenses
Inquiry skills focus	Developing hypotheses Forming coherent arguments
Scientific literacy	Explain phenomena scientifically
Assessment methods	Classroom dialogue Worksheets

Students carry out experiments using lenses to investigate how they produce images on a screen, in particular considering the size of the image formed, and what factors influence this. Students build upon their prior knowledge of how light travels, and what occurs as it passes from one material to another. Students also consider the formation of images when using a magnifying glass or lenses for correction of vision.

This unit was trialled in three countries, producing four case studies of its implementation (CS1 Ireland, CS2 Ireland, CS3 Greece and CS4 Slovakia). All the case studies were implemented by teachers who had some experience of teaching through inquiry but the students involved had generally not been taught through inquiry.

CS1 Ireland, CS2 Ireland and CS3 Greece involved lower second level students: CS1 Ireland was a class of 22 girls working in groups of three, CS2 Ireland was a class of 22 boys aged working in pairs and CS3 Greece involved a mixed gender class of 24 students working in groups of three or four. These case studies describe double lesson periods, approximately 80 minutes each for CS1 and CS2 (both Ireland), and 120 minutes for CS3 Greece. The students in CS4 Slovakia were a class of 28 mixed ability and mixed gender upper second level students aged 17-18 years old, working in groups of two or three, and the case study describes a single 45 minute lesson.

Through the four case studies, details of assessment are provided for the four key SAILS inquiry skills, namely developing hypotheses, planning investigations, forming coherent arguments and working collaboratively. Some teachers also found this unit useful for assessment of scientific literacy, looking at students' ability to explain the concepts of light using scientific terminology. The main methods of assessment were classroom dialogue, where the teacher could provide formative feedback on the fly, and evaluation of students' worksheets, often using rubrics to distinguish performance levels.

The inquiry approach adopted by the teachers was a guided inquiry approach, with students completing the activities being guided by the questions in the worksheet and the teacher’s questions. All students completed the activities working in small groups and peer discussion was encouraged and facilitated. Teachers observed that the worksheet questions encouraged interactive discussion among students. Teachers circulated between groups probing student conceptual understanding through directed questions to individuals.

Within the four case studies, the inquiry skills of planning investigations, forming coherent arguments, developing hypotheses and working collaboratively were assessed in different ways, with some teachers using the rubrics proposed in the original unit. Additionally the content knowledge and evidence of scientific reasoning/literacy was assessed through the student worksheets and verbal responses.

Below you can find the full inquiry and assessment unit for download (excluding the case studies), as well as an archive containing all the case studies.

Unit booklet Case studies

CS1 Ireland

Concept focus	Sources of light Understanding shadows
Activities implemented	What are sources of light? Understanding shadows
Inquiry skills assessed	Developing hypotheses Forming coherent arguments
Assessment methods	Classroom dialogue Worksheets
Level	Lower
Age	13-14
Prior experience with inquiry	No experience

Two activities from the Light SAILS inquiry and assessment unit were trialled in this case study – looking at sources of light and formation of shadows. Skills identified for assessment were developing hypotheses and forming coherent arguments. Skills were assessed through evaluation of student worksheets, using a three-level rubric to evaluate performance level. Students were given verbal feedback on arguments presented in class.

Download case study

CS2 Ireland

Concept focus	Developing inquiry skills
Activities implemented	What are sources of light? How does light travel? Understanding shadows Exploring white light and filters
Inquiry skills assessed	Forming coherent arguments
Scientific reasoning	Argumentation
Scientific literacy	Explaining concepts scientifically
Assessment methods	Classroom dialogue Worksheets
Level	Lower
Age	13-14
Prior experience with inquiry	No experience

In this implementation, the focus of the lesson was on development of inquiry skills, as the students had no experience in inquiry-based learning. Assessment focused on students’ scientific literacy, evidenced by their ability to explain the phenomena observed in a scientific way. This was achieved through classroom dialogue to review their prior knowledge, teacher observation, group discussion and evaluation of their investigation design. The teacher used worksheets to grade their level of understanding.

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CS3 Greece

Concept focus	White light and primary colours
Activities implemented	Exploring white light and filters Exploring primary colours
Inquiry skills assessed	Planning investigations Forming coherent arguments
Scientific reasoning	Drawing conclusions Making comparison
Assessment methods	Classroom dialogue Teacher observation Worksheets
Level	Lower
Age	12-13
Prior experience with inquiry	No experience

This case study looked at two activities – exploring white light and filters and exploring primary colours. In addition to prisms, the teacher utilised some online resources to aid student learning and encouraged students to observe pixels in their mobile using a magnifying glass. Classroom dialogue was a key method for assessment of skill in forming coherent arguments and planning investigations, while the teacher also evaluated students’ worksheets using the rubrics proposed in the unit.

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CS4 Slovakia


Activities implemented	How does light travel? Understanding shadows Exploring refraction
Inquiry skills assessed	Forming coherent arguments Working collaboratively
Scientific reasoning	Making reasoned decisions
Scientific literacy	Application of scientific concepts
Assessment methods	Classroom dialogue Self-assessment Worksheets
Level	Upper
Age	17-18
Prior experience with inquiry	Some experience

During this inquiry activity, the teacher observed group work and asked additional questions, guided students to the right approach, or provided a short explanation of physics background, if needed. The teacher tried to use formative assessment as much as possible, especially during group discussions and forming of conclusions, and provided feedback to the students about their progress. The teacher analysed students’ worksheets after the lesson, with a focus on providing short comments and tips for improvements.

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Reflection and refraction. What do I see in a mirror?