## Dogs and Gobstoppers

After a holiday and being home sick last week, it was great to be back in the classroom today.   The bell work turned into about half of the class as they discussed how to set up experiments with identifying the independent and dependent variables and then developed a hypothesis.  The bell work question was “Does the type of collar I use on my dog affect how much he pulls me when I walk him?”  They figured out that they were changing the type of collar, so it must be the independent variable.  And then they realized that the amount the dog pulled would be the dependent variable–but, they had to figure out how to measure that.  Most decided that they would measure how much slack in the leash there was.  One student wanted the precision of a spring scale to measure the force of the dog pulling.  They’ve learned that their hypotheses need the words “if,” “then” and “because.”  Most hypotheses were along the lines of “If the type of collar is a choke collar, then my dog will pull less because he doesn’t like to be choked.”

I think the activity went a bit longer than was originally intended for “bell work”, but the students are starting to understand the scientific process a little bit better and how to apply it to questions they want to answer.  This will tie in well to the problem based lesson I had planned for next week.  I’m going to give them some sort of mythbusters type question (yet to be determined), and let them figure out a way they could test the myth.  We’re starting their science fair projects in 2 weeks and want to set them up knowing how to answer their questions.  Now we just need to do some work to get them to ask some good questions–especially since most of the questions they go through in learning the “scientific process” are weak questions, to say the least.  We plan on having a few categories to direct them to their own questions.

The rest of the class time had a few students start a new lab about gobstoppers, while the majority were finishing work from yesterday.  This made me wonder how in the world the teachers manage having everyone go at different paces.  There is such a huge learning diversities and abilities, it seems entirely overwhelming getting through the material under these circumstances.

A couple highlights:

• One student couldn’t think of how the results of their previous leaf ripometer experiment might have an application to something else in their life.  I had him tell me what the results were and why he thought certain leafs were tougher than others.  He decided that the sun exposure affected the toughness of leaves, and that maybe there were some connection to our skin and sun exposure.  For going from the complete blank look and starting into “shut down” mode of not knowing what it’s asking, or what the “right answer” was, I thought that was a great step.
• One student asked about the science fair project and if they could pick their own question.  She was very adamant about not doing a volcano, because it was “old”, i.e., it’s been done a million times so it’s boring and it doesn’t really answer any questions.  So, hopefully this enthusiasm will continue when we get into the difficult part of actually guiding them to come up with some meaningful questions.