Heat Transfer

For this inquiry experiment, I used cotton cloth, a wool scarf, a fleece scarf, and aluminum foil to test which material was the best insulator of heat.  I filled four identical mugs with one cup of 130 degree water.  I covered the mugs with the four materials and then waited for thirty minutes.  After the half hour, I measured the temperature of each cup with a thermometer and found that the water covered by the cotton cloth was 100 degrees, the water that had been covered with the aluminum foil and the wool scarf was 82 degrees, and the water that had been covered with the fleece scarf was 78 degrees.  My results were surprising to me, and not at all what I had expected or predicted.  I definitely want to repeat this experiment on my own to make sure that my results stay consistent.  I tried to keep every other variable constant, but with my prediciton being so far off the mark, I wonder if I did something wrong by mistake.  I always tell my students that it is okay to be wrong in science as long as they communicate that in the conclusion.  We discuss that doctors and researchers are wrong daily about what type of medicine may cure a disease, but they do not let that stop them from continuing their research.  It is important to communicate what works and what doesn't so that others can try something new instead of repeating something that is known to not work.  In this experiment, I was wrong.  I would love for my students to complete this experiment to find the material that is the best insulator.  Having the opportunity to choose the materials that are tested would be fun and interesting for the students, and truly engage them in the experiment.  I would also love to complete the activity in the What's Hot? What's Not? article.  The hook of the story, and then the engagement of testing actual porridge would immediately grab and hold students' attention.

Guided Inquiry Lesson

This week, I focused on the research question “what is the effect of large objects colliding with smaller objects?”  Looking through the science kit, I chose the marbles due to the varied size.  I carefully measured and placed the marbles one foot apart from each other.  I allowed my twin sons to lightly push the marbles toward each other from their starting points.  Because my sons are identical, I thought that this would be as controlled as possible.  A qualitative observation that I made was that the larger marble pushed the smaller marble in the direction that the larger marble wanted to go.  I could directly see the transfer of energy.  However, even though the larger marble won in directional force, the smaller marble created enough resistance to slow down the larger marble.  A variable that I identified was the surface on which the marbles were tested.  A carpeted floor was used for the experiment, as opposed to a hardwood floor that would provide less friction for the marbles to stop.  On the carpeted floor, I made a quantitative observation that the smaller marble moved four and one half inches.  We repeated the experiment a total of three times to ensure accuracy.  The second and third trials provided consistent results, taking into account the variable of human error.

            Engaging in the guided inquiry experience helped me to further my understanding of this scientific concept of unbalanced forces and momentum. I found it very beneficial to be able to look through the kit and determine what materials I would need to best answer the research question.  I reflected back to my own classroom and wondered how beneficial and interesting an inquiry experiment like this would be for my students.  I think it is worth mentioning that this level on the inquiry continuum reaches the higher levels of Bloom’s taxonomy that are so important for students to show that they can apply and evaluate what they have learned. 

            A challenge that I faced during this inquiry was making sure that only one variable was changed and that all other variables remained controlled and constant.  Because my sons were the ones to release the marbles, instead of something more controlled, human error played a part in my results.  I could foresee this being a problem for my sixth grade students.  Another problem that I could see arising would be students wanted me to tell them what to do instead of embracing this level of inquiry and designing their own investigations.  I think that students’ creativity and ingenuity has been stifled in the age of high stakes testing and in order for them to regain these important elements of science and technology, more practice in guided and open inquiry will need to take place.