One of my favorite things to talk about with my colleagues is the use of lecture demonstrations in teaching. There seems to be a push in my district to stop using chemicals whenever possible and get to computer simulations and video in place of wet chemistry. I don’t think they are thrilled with me since I can’t envision ever taking the chemistry out of chemistry.
There have been a TON of great ideas for guided inquiry (modeling instruction(link is external), POGIL(link is external), Target Inquiry(link is external), etc.). I do a ton of guided inquiry in my classroom. I have engaged in professional development on facilitating group work (through POGIL) and read what I hear is THE book on group work (which really is quite good- “Designing Groupwork(link is external)”).
A perfect storm starts to form. We are on the concept of moles and I have some students who are struggling mathematically. It is a rough time of year to get kids excited. Many students are struggling with ACT and SAT prep and as a teacher, I am tired of test...test...test. Also, I had about two dozen 2 liter bottle "pre forms" that I needed to find something to do with.
The chemistry of silver and the process in which silver becomes tarnished is explored. Take a new look at an old JCE Classroom Activity.
Flinn Scientific has a great elearning video series. Many of the videos have master teachers demonstrating some great labs and techniques that they do in the classroom. A general theme in many of the videos seems to be combining demonstrations, labs, calculations and lab practicals. The nice part about what occurs is that for whatever concept the students are doing, it is not enough to come up with an answer on paper. They have to use that answer for a prediction and then see if they are correct actually checking and manipulating material. This idea has added a new dimension to my classroom. Students who are tired of "pen and paper" work now get to get up and use their answers to mass something or find the volume of something and see if they are correct. I have tried to add more of these to my lessons.
As we pilot new laboratory activities in the classroom, my students and I are in constant dialogue. Not only do they leave feedback at the end of each lesson (what did you learn, what was your favorite part, what was you least favorite part), but we talk throughout the experiment. Recently our discussion was focused on the questions.
In my IB Chemistry class, my seniors were finishing up independent investigations for their Internal Assessment a few weeks ago when something cool happened. One of my students was using silver nitrate and potassium chromate for a titration. This is notable to the story here because the endpoint is marked by the formation of silver chromate as a precipitate, with a deep reddish color. I overhead the student showing his reaction to another student, with both of them commenting on the cool colors involved.
First, I would like to thank all those who commented on my last blog. For the record, I was wrong. Initially I looked at Linus Paulings early papers as he worked on electronegativity. Much of the work focused on connecting the concept to bond energy. There were some great comments posted to the blog. Probably one of the best was explaining how the concept of electronegativity presents a model for bonds. It is not an observable quantity. This really helped me explain it better to my students. As the commentor posted, all models have limitations. Second, the person commented that in Linus Pauling's General Chemistry book published in 1970 (Dover Publishing) that he does indeed talk about the differences in electronegativity to discuss a type of ionic and covalent character. I stand corrected.