pproach (Lorsbach and Tobin, 1992) - rather than the more mechanical approach to practical work which is sometimes adopted (Woolnough and Allsop, 1985; Hodson, 1990).
An evaluation of the use of concept cartoons was carried out by teachers and researchers working in a variety of educational settings. These included school teachers covering the 5-18 age range, college lecturers, teachers working with children with special educational needs, teachers of English as a second language and in-service providers. These teacher-researchers were invited to use the cartoons and to evaluate them critically.
Data was collected by a combination of participant and non-participant observation, tape recordings, questionnaires completed by the researchers, oral and written feedback from the learners involved, interviews with some of the researchers and interviews with some of the learners. The groups observed have included primary and secondary pupils, higher education students, parents and teachers. In many cases authentication of the data was possible using a combination of investigator and methodological triangulation (Denzin 1970).
Action research with our own teaching groups allowed us to discuss alternative formats for the concept cartoons with students and teachers as well as providing further evaluation data. This led to a number of developments in the format of the concept cartoons. These include a shift from negatively-worded to positively-worded statements, a shift from statements to questions and a shift from single alternatives to multiple alternatives.
The concept cartoons have also been presented to a variety of audiences at local, regional, national and international Conferences. This has been helpful in gauging the views of a larger cross-section of the teaching population, since our main sample of about 80 teacher-researchers consisted of volunteers who were interested in using the concept cartoons.
Evaluating the use of the concept cartoons
The concept cartoons were intended to stimulate discussion and to make the learners' ideas explicit through this discussion. The data consistently indicated that the concept cartoons were very effective in this elicitation process. Many teachers commented on how the concept cartoons readily gave them access to the learners' ideas and revealed the learners' conceptual development - "the ideas are so explicit they do not require further probing" was one teacher's comment. One instance of this was an eight-year old child's description of why snow is bright - "Sun pings onto snow, then pings off again into your eyes". A teacher working with children with behavioural difficulties noted that "the children were less inhibited than when asked questions verbally" and other teachers commented on how the concept cartoons were particularly useful for encouraging discussion amongst pupils who are reluctant to reveal their own thinking.
Many of the teachers involved observed examples of restructuring in a range of teaching situations. Teachers commented on how the concept cartoons promoted cognitive development in the learners. Learners mentioned sometimes changing their minds when they discussed the concept cartoons - how they "had thought one thing but now believed something else". The concept cartoons appeared to provide a stimulus which frequently led to the learner's ideas being modified and developed.
Linking together elicitation and restructuring
There is evidence that the concept cartoons have drawn together the elicitation and restructuring phases of the constructivist teaching sequence. Several clear examples were observed where ideas were being expressed and then modified during the discussions and investigations which emerged from the use of the concept cartoons. In each instance the concept cartoon was the starting point for the discussion and in many no further input to stimulate change in ideas was made by the teacher.
One group of 7-8 year olds quickly agreed that there would be no light if clouds covered the sun (see Figure 3) and then modified their ideas through discussion withi