WWW Site for John Lawrence Bencze, Associate Professor (Emeritus), Science Education, OISE/University of Toronto

Science Teaching & Learning
'Conceptual' Education

'Expressing' Ideas

e.g., Encouraging students to say what they know

Welcome! This page provides perspectives and practices useful for encouraging students to express their ideas about topics in school science & technology. "Expressing Ideas" is the first of three phases in my framework for students' 'conceptual' education; that is, for encouraging them to reconstruct their conceptions about 'products' (e.g., laws & theories) of science & technology. If you have ideas, questions, comments, etc. about anything here, write to me.
Student Assessment.

Rationale for Expressing Ideas
Often, based on constructivist learning principles, students begin teaching and learning sessions already possessing 'ideas' about topics that the teacher intends to discuss. For example, if a teacher planned to teach students about plant growth, students may already know that they need water and light, for example. If so, the teacher would not have to teach such information. On the other hand, students might also have the idea that plants growth towards the sun because they are 'attracted' to its energy. They may believe that plants 'choose' to grow towards light energy. This is not, however, an explanation that has been supported by scientists. If the teacher were to simply directly explain to the students that plants grow towards the sun because of hormonal responses to light in the process of phototropism, research evidence suggests that students might understand such an explanation, but continue to believe their own pre-instructional conception; e.g., that plants 'want' to grow closer to the light. Such a view is not, necessarily, bad. However, it has not been accepted by scientists as a 'causal' explanation. Students may need to decide ('judge') which explanations are best. This may be particularly important if students are to pursue careers in science and/or technology relating to plants. A problem is, however, that students' pre-instructional conceptions may be sub-conscious and, when the teacher teaches an alternative view (e.g., phototropism), the student does not directly consider changing his/her view. Asking students to 'express' their pre-instructional ideas can help them become more aware of their own conceptions and, when alternative ideas are posed (e.g., Learning Ideas), consider changing them (e.g., Juding Ideas).

Some Constructivist Learning Principles
  • Each person has had a unique set of experiences and, therefore, will have a unique set of ideas in the brain;
  • There is considerable evidence all learners attempt to relate new ideas to those in their memories. This may cause them to, for example, see or concentrate on different aspects of a phenomenon than would other learners;
  • Often, a person's ideas are subconscious; that is, they are not aware they have them or that they affect them;
  • Without making ideas conscious, a person may not confront their own ideas and, as a result, not have an opportunity to change them;
  • Once teachers have identified some pre-instructional ideas that students hold, they can plan lessons to encourage students to consider alternative ideas.
(Go to top)

Strategies for Encouraging Students to Express Ideas
Encouraging students to express ideas is a 'stimulus-response' process, in which the teacher provides one or more stimuli - which lead students to indicate (e.g., via talking, writing, drawing, etc.) their current concepts relating to the stimuli. A typical situation in which a teacher stimulates students' expression of ideas is given below:

Students could be shown several bean seedlings, in various stages of development, as show at right. Whenever possible, it is important to use concrete materials - especially with young students. The teacher will give students some directions for responding to the materials (e.g., plants), but will try not to be too directive - since the goal is to stimulate free expression. In other words, the goal is to promote divergent, as opposed to convergent, thinking. Learning control should be largely student-directed and open-ended. The teacher might, for example, ask students to: 'Write down what you know and want to know about these plants.' After students have responded to this more divergent type of request, the teacher could be a bit more directive (convergent); asking students, for example, to: 'List some environmental conditions that might harm the plants and explain ways in which the plants might be harmed.' This sort of request may highlight WISE Problems, which might lead students to eventually conduct science inquiry and/or technology design projects that provide evidence for their ideas - and promote WISE Activism.

Teachers have many choices about the kinds of stimuli to use for encouraging students to express their ideas. Different students often prefer different approaches to teaching and learning. It is thought, for example, that there are multiple intelligences; that is, general categories, such as 'Verbal-Linguistic Intelligence' and 'Visual-Spacial Intelligence' - and that each person has a unique set of these. For at least this reason, it is important for teachers to use a variety of stimuli types. Teachers can, therefore, use stimuli that involve speaking, writing, listening, drawing, singing, movements, etc. Expression of ideas can, as well, occur outside classrooms; e.g., on nature walks.

An interesting type of stimulus is the concept cartoon, one of which is shown at left. This combines
'Verbal-Linguistic' and 'Visual-Spacial' intelligences. Teachers could show students different concept cartoons relating to a topic and ask them to discuss among themselves which response (in the cartoon) might be best and then vote on them. Although there is a great deal of evidence, of course, for the third explanation at left ("One side always faces towards the earth"), it is still important for the teacher to leave this activity open-ended; that is, to ensure that students feel comfortable expressing their ideas. Having the teacher then say something like, 'These students (pointing to them) were right; the rest of you had it wrong,' is unlikely to encourage student expression of ideas.

A significant problem for teachers may occur if students have not had much experience with expressing their ideas. Students may lack confidence and skills to do so. This is likely if their previous education has been largely TD/CE. It is important, therefore, for students to have a Skills Education and, particular to this phase of learning, lessons and activities to enable them to develop skills for expressing ideas. Students may learn, for example, how to construct concept maps like that at right. Similarly, they may learn how to develop: cause-result questions, predictions and hypotheses, drawings and models to depict their thoughts, and arguments to support their claims.

(Go to top)

Particularly for younger students, it is important to ask students to express their pre-instructional ideas in relation to concrete phenomena; that is, objects and events with which they can directly interact with their senses. Some typical phenomena with which students might react regarding common school science topics are given below;
Structures & Mechanisms
Earth &
Space Systems
  • Mealworms
  • Ant colony
  • Aquarium fish
  • Pet mammals, birds
  • Humans
Green Plants 
  • Seeds, seedlings
  • Leaf collections
  • Fruit
  • Flowering plants
  • Mold on bread (sealed!)
  • Yeast, sugar, water

  • Pond water and microscopes
  • Live specimens from a supplier
  • Preserved specimens
Monera (e.g., Bacteria)
  • Preserved specimens & microscopes
  • Microslides and viewers
  • Bacteria on agar plates (caution!)
  • wood
  • metals
  • glass, mirrors, lenses
  • rocks, minerals
  • cloth, synthetics
  • water
  • vinegar
  • syrup
  • air in balloons
  • air pockets in water
  • helium balloons
  • carbon dioxide trapped above water in containers
  • salt water
  • sugar water, pop
  • oil & gas
  • plastics
  • alloys
  • elastic materials
Heat Energy
  • heat from candle
  • heat from alcohol burner
  • heat from rubbing friction
Light Energy
  • magnified light
  • dark vs light clothes
Electrical Energy
  • electric circuits (batteries, bulbs, & wires)
  • lightning
  • various magnets
  • electromagnet in doorbell
Static Electricity
  • rubbed balloons
  • hair & sweaters
Moving (Kinetic) Energy
  • wind-up toys
  • falling objects
  • screwdrivers
  • pliers
  • hammers
  • syringes (with water or air inside)
  • pulleys
  • ramps, stairs, ladders
  • teeter-totters
  • bicycle gears
  • jungle gym
  • bridges
  • tents
  • igloos
  • different soils
  • salt, fresh water
  • rocks, minerals
  • weather
  • animal adaptations
  • seasons
  • day/night
  • satellites
  • telescopes
  • rockets
  • solar systems
(NOTE: The Ontario curriculum guidelines contain many suggestions for specific experiences in each unit.)
(Go to top)

Student Assesment & Evaluation

Teachers should keep in mind that the purpose of these exercises is for students to express their ideas. Using Lock's model for analysis of lessons (at right), these activities should be, primarily, student-directed (SD) and open-ended (OE). There may, however, be a little TD to get the students to react to the phenomena. Nevertheless, because the emphasis is on getting students to freely express their attitudes, knowledge, skills, etc., teachers should limit their assessment & evaluation of students' work to judgements of their effort. Teachers should be careful with this; they should know the students' personalities first. As well, it may be foreign to some students' cultures to openly express their ideas, and that should be respected. Also, it should be noted that the ideas students express at this stage may not match those of scientists and technologists. For example, refer to: About Alternative Ideas and Things People Said. Some people would be tempted to call such non-'scientific' ideas 'misconceptions' or 'naive ideas.' Both of these expressions are derogatory and are likely to discourage students to express their ideas. Perhaps a better way of describing them are to refer to them as 'alternative ideas' or 'students' ideas.'

Note: This 'learning-control' grid is
elaborated @ Lock.

(Go to top)