8.3 Predict.Observe.Explain
There are many, many ways to organize hands-on science lessons. Most of these can be made to work fairly well; most hinder learning when they are used rigidly and exclusively.
One fairly simple procedure, called POE, regularizes a small part of scientific inquiry. It is used when students have some phenomenon to investigate, for example, seeing how many pennies they can drop into a full cup of water before it spills over. The POE procedure benefits learning in several ways.
The students first divide a sheet of paper into three parts, labeled like this:
P
O
EDepending on the activity, students may do some preliminary exploring, but they do not initially try out the key phenomenon. Instead, they first write a prediction, P. This may involve some quantification, as in "We can put three pennies in the cup before it spills," or it may be just a qualitative prediction.
Then, they carry out the experiment or explore the phenomenon in question. Under O, they write their observations, which may include drawings, measurements, or narrative accounts. Finally, under E, they write their explanation for the effects they observed. When the observations are counter to the predictions, there is greater opportunity for thinking in the explaining part.
It is important to adjust expectations for the three parts appropriately depending on the experiment and the students. Writing, or drawing, something is usually better than holding out for a precise or conventional account. If students have difficulty getting started, it is better to let the writing grow out of talk than to insist on some formal process. Sometimes, an explanation can start with just a more detailed description. In the pennies experiment, a grade six student might write "The skin on the water just got higher and higher," as a first explanation.