water. The conclusions drawn from the experiment give the student the opportunity to demonstrate his understanding of the results, awareness of the limitations of his methodology, critical thoughts about how to improve the experiment, and ideas about other directions he would like to take his work. There are times when a student’s hypothesis is not confirmed by his experiment and these are often the moments when great learning occurs. There are a variety of reasons for an incorrect hypothesis. Sometimes students make measurement Figure 2: Graph of data collected by Dylan Rose.
errors, or the hypothesis was not carefully thought through, but as Alexander Gottdiener’s (Form II) experiment shows, even a
traveled by the board (Figure 2). In other experiments the data may not make a linear graph, but a line of best fit and the linear equation is still found and interpreted as an approximation. While Form II students create computer generated graphs for their website demonstrations, they must calculate their slopes by hand. Furthermore, all younger students must draw their graphs by hand, a discipline that reinforces important graphical concepts such as the need for uniform scales, clear numeration of scales, correct labeling, and accurate point plotting on the
thoughtful hypothesis and a careful experiment may not be enough. Sometimes nature simply does the unexpected. The hypothesis stated that fewer birds would come to the feeder as it was moved further away from a tree and into the open field. Not only was the hypothesis incorrect, but amazingly, the exact opposite occurred! In fact, more birds came to the feeder to eat when it was in the middle of the field. No birds came when it was under the tree until the six five minute trials occurred at the tree.
Discussing sources of error is a major part of the conclusion.
graph—skills not exercised when the computer makes the graph
In student work there can be all manner of errors including the
for a student.
limitations of the measurement instruments, inherent instability
Increasingly, students are using video to help document and
of the variables being measured, student mistakes, and of course
present their work, as a scene shows from Aadir Khan’s (Form
catastrophic failures of the setup (all the plants died over the
II) experiment analyzing the formation of emulsions of oil and
holidays when we went on vacation).
Charles Pink, Grade 5
Marwan Nsouli, Grade 5
Andrew Medland, Grade 5