-by Carolyn Armstrong, Grade 6 Math/Science
*originally posted in February 2012
Objective: Students work as true scientists through rigorous scientific exploration and experimentation.
The Project in a Nutshell: Test and compare the water absorbency of yellow (healthy) pine and blue (fungus-stained) pine wood.
How it came to be: One our parents approached me about taking on a special project that was brought to her attention through a fellow member of ABEC: Alberta Building Envelope Council. The Council focuses on the building envelope, which basically means keeping the outside out and the inside in. The idea is not necessarily to look for energy alternatives, but to reduce energy consumption in the heating and cooling of buildings.
One of ABEC’s members proposed that a study be done concerning the water absorbency of blue wood. He was looking at high school or post-secondary institutions when it was suggested that he explore a younger group of scientists - hence my Grade 6 students.
The Process: As a class and with adult support, we were able to obtain several samples of blue and yellow wood. One of our students’ dad help us out build the water testing trays and a wood suspension system and cut all our samples of wood to the required length. The students helped secure the brackets to the top of the wood and prepare them for soaking. First we weighed all our dry samples and then dried the blue wood samples for 8 hours in 200ºC convection ovens. Note: The blue wood was freshly milled whereas the yellow wood had been dried over a longer period of time. We graphed our results and were surprised to see how much weight the blue wood lost. We also noted one sample appeared to gain weight so initiated the conversation around outliers and human error.
Next we waxed each sample carefully on four sides leaving the ends open. This would prohibit evaporation and create a wicking effect. Then we carefully suspended the samples in the water trays so only about 1cm of the wood ends were immersed. Over the next several days we took timed measurements of the weight gained by each sample. The students recorded their weights in “Excel” or “Numbers” spreadsheets. When finished our testing, each student had to analyze and graph his or her results. Using the scientific method, they completed their lab work.
Follow-up: We had many discussions around variables, outliers and scientific testing and viable data collection. We realize this will be an ongoing project because our sample set was not big enough and we are not yet ready to “publish” our results - but they do look promising!