Predict, Observe,Explain in Year 8 Science

Towards a Thinking Classroom, page 32
November 1996

Vivienne Sullivan, Avilia College

Introduction

In 1995-6, six teachers at Avila College, a Catholic girls school in Melbourne, worked with Jeff Northfield and Ian and Judie Mitchell of Monash University in a PAVOT (Perspectives and Voice Of the Teacher) project supported by Australian Research Council funding. More details of PAVOT can be found in PAVOT The Perspective and Voice Of the teacher . More details of the Avila project and the teachers reflections on the impact of the project on them can be found in The Avila PAVOT Project . This article comes from a book (Towards a Thinking Classroom; PEEL Publishing) that they wrote at the end of the project.

The group instigated a cross-curriculum approach to tackling the problem of student passivity. They drew on Chapter 10 of the second PEEL book, Learning from the PEEL Experience, (Baird and Northfield, 1992). This chapter describes 76 teaching procedures used and developed by PEEL teachers. They chose to focus on the 18 procedures that this book argued were designed to encourage the type of students thinking summed up by Concern #4 (p.212): "Students won t try and really understand the work they don t know how to think". The Avila teachers took 11 of these procedures, tested each of them in several classrooms and then evaluated them against Concern 4, both after each classroom test and then more generally using a PMI (see B15). This article is one of 5 that tested Predict, Observe, Explain (see B1).

One value of their work is that it provides the best-documented account we have of teaching procedures bouncing around a PEEL group from teacher to teacher and subject to subject., often mutating and evolving, developing different variations and emphases in the process. To retain this feature we have linked this article to the others in that chapter (see Predict, Observe, Explain in Year 10 Total Surface Area and in Year 10 Quadratic Equations, Year 9 Maths and Year 10 Geography) and included their general introduction to and evaluation of the procedure. We have also included the "thoughts" that were added to the chapter by their academic friends Ian and Judie Mitchell.

Eds

Testing Predict Observe, Explain in Year 8 Science

Aims:
The class had studied convection currents in liquids. I wanted students to use that theory and the observations from the practical activities to explain heat transfer in gases. By using this strategy I hoped to challenge them to think about the material they had already learned before moving on to its applications.

Method:
The nature of a "predict, observe, explain" activity was outlined in general terms. Students were then shown a ventilation apparatus (glass-fronted black box with two chimneys with a candle under one of them). The fact that we cannot see air but that we can visualise its movement if we use smoke was discussed. The students were then told that the candle would be lit and that the smoking taper would be placed firstly above one chimney and then the other. They were then asked to record their predictions about the direction of smoke movement by drawing diagrams and also writing a paragraph. These predictions were discussed. The demonstration was then carried out and observations recorded. Reasons for the behaviour of the smoke were discussed and comparisons drawn between this and the experiments performed previously on convection in liquids. A written comparison was made between predicted and observed results.

Observations:
Relatively few students had predicted the results accurately.
A small number had concentrated on smoke coming from the candle and so were confused by this. (When I repeated this with my second class I made a point of referring to it as a smokeless candle, and the confusion was avoided.)

The "Explain" part of the exercise was well written by about one third of the students. They tackled the conceptual errors that they had experienced in the "Predict" phase, and showed some real progress in their understanding of the experiment. Comments like "I forgot that the hot air would rise because the cold, heavy air would push it away" were typical. Another significant group tried to come to terms with the background theory but gave comments that were flawed, for example "I forgot that the heat, being strong and hot, would push the air..." The others who had predicted inaccurately wrote explanations of their errors which just restated the results. For example: "I was wrong because I thought the smoke would just float around and instead it ..."

Evaluation:
Even though this type of approach is a natural extension of what we do in Science all the time, it was very valuable to set it up as a formal activity. It provided a good basis for structured discussion.
The effectiveness of the exercise as a learning tool was discussed with the students and feedback sought. It was judged by the majority of the class to have required more thought on their part than if the demonstration had just been shown to them. I feel confident that this is the case.

Overall Explanation of Predict, Observe, Explain

Pluses

· really extends more able students

· areas of misconception are drawn out

· students are challenged out of their complacency

· gives students ownership of the knowledge

· allows for the use of writing as an alternative form of communication (e.g., in Maths)

Minuses

· nature of the set task is very important an inappropriate choice can easily lead to student frustration because of insufficient background knowledge upon which to base predictions

· if only those who make incorrect predictions have to explain/write then students struggling with the content can be even more isolated

· difficulty can be experienced in motivating students to apply themselves to the "explain" part of the procedure

· students may be disadvantaged in Maths when they are required to write about it

Interesting

· having the student write explanations regardless of whether the prediction is incorrect advantages class management because:

i) all students are kept occupied

ii) those who predicted correctly but with invalid reasoning can be identified

· the procedure does not lend itself well to a protracted task as this compounds any problems with motivating students to write the "explain" section

· while thinking may be promoted, there is no guarantee that this will be quality thinking leading to valid responses

Thoughts: Ian Mitchell

One of the most fascinating, even exciting aspects of PEEL for me has been the way teaching procedures mutate, evolve, adapt and develop in new directions as they jump around from teacher to teacher and subject to subject. Sometimes the extent of evolution (to continue the biological metaphor) is sufficient to produce a new species (procedure) that requires a new name. The rules , or rather pieces of advice that accompany a procedure, such as Do not grade the predictions in a POE , also evolve with the procedure and it may be that the reasons for the original advice no longer apply to a particular mutation. Reflecting on the question: Was this helpful to learning (and why)? often provides reassurance to teachers who wonder if what they did was allowed . These five accounts provide a very nice illustration of this mutation of a procedure. POEs were developed to help students make links between school ideas and what they already believed. Vivienne s activity is a classic (and original) example of a POE that does this well in the domain where they were first developed - Science. Rola, Rosemary and Sue have all adapted the procedure in different ways. Rosemary s two activities both involve a series of POEs where, to me, the challenge for the teacher is to set a sequence of tasks that allows for steady discovery, exploration and reinforcement of the handful of factors that affect the graph shapes. In Science, POEs are usually most effective when most students predict incorrectly - they are keen to work out why; Vivienne s activity illustrates this well. In Rosemary s and Rola s examples, with many Ps, each of which build on the previous Os and Es, there needs to be a reasonable frequency of success to encourage persistence at the next one. I thought Rola was a bit hard on herself; her activity actually had two different, and equally important ways of being different from the text: one, which she gave some nice examples of, was to be wrong and work out why. The other was for the prediction to be mathematically correct, but merely expressed differently from the text. An example of the latter might be the formula for the surface of a (cylindrical) soup can. A student who thought about adding up the areas of the top, the sides and then the bottom might write:

SA = r2 + 2 rh + r2
This is correct, but the text may collect like terms and factorise to rearrange this as:
SA = 2 r (r + h)
Sorting out whether or not these are the same is good maths.

Sue had an activity which had mutated in a quite different direction, one which was likely to make both library research as well as the subsequent sharing of the results far more purposeful and effective by bringing up what each student already knew or believed in the area. The reflection on learning that she extracted from this and her follow-up on Disasters is a perfect illustration of one of the original goals of PEEL - developing students who know how to learn well.

Rosemary s comment about trust raises a crucial aspect of student change: most good learning behaviours (such as publicly sharing predictions) are high risk ones for the student, fostering them is dependent on building trust between students and their colleagues and students and the teacher.