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The beginning inquiry about ‘water in things that seem dry’ was good and open-ended.  It would allow kids to pose answers and questions and therefore, feel a part of the lesson.  Showing us the blue crystals and then leaving us with the question, “What is the percent water in copper sulfate” was clear and unambiguous.  When I looked up the percentage on the web, I found the material to be named with ‘penta-hydrate’ as a suffix.  For those who thought that there was no water in the compound, it would have been clear from the full name that there was!!  So, a little deception is a good thing!!  I am relatively comfortable in both a lab setting and with the math involved, so my in initial  ‘confusion’ level was minimal. 

The lab was set up well.  There was a lot of space between stations and the area for the lab materials was clear and open.  Paul was an excellent and willing resource for advice and general questions.

My group’s results, however, have left me very confused, literally and metaphorically.  Having looked up the appropriate answer, I am now considering the myriad of reasons for our error.  I am confident our methodology was sound, so I am leaning on ‘random error’ as the cause for our answer.

The wide range of values the group generated would be excellent fodder for inquiry discussion post lab.  Having the students rewrite their procedure for another group to use is an excellent idea.  The subtitle of my favorite book in grad school was, “To Teach Is To Learn Again”.  I liked Joyce’s idea of a little spirited competition, quickest, simplest, most accurate…