COMPILATION: Chemistry teachers like the Physics First sequence

COMPILATION: Chemistry teachers like the Physics First sequence

Chemistry teachers like it when physics is taught in 9th grade, using Modeling Instruction! Read the post below, by two high school chemistry teachers who've taught at Clayton High School.

Background: the Physics First sequence is used at Clayton High School, a public high school near St. Louis, Missouri. Rex Rice, the science department chair, introduced Modeling Instruction in the mid 1990's. Since 2001, the 5 freshman physics teachers use Modeling Instruction. Student scores on the Force Concept Inventory are MUCH higher than when conventional physics instruction is used, even though ALL 9th graders are included, rather than the top 25% who typically take 11th or 12th grade physics!

The posts referred to below are downloadable at <

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Date: Wed, 16 Apr 2003

From: Milbry McDowell <>

Subject: Chemistry Before Biology

Sender: Modeling - Modeling Workshop Teachers <>

To:

As both a Clayton HS Alumna and a former Clayton teacher, I have read with interest the recent postings regarding Physics first at CHS.

Clayton's curriculum has been Physics first followed by Chemistry and then Biology for the honors students for at least 30 years. I was a student at Clayton in the late 1970's, and in the honors freshman course, "Quantitative Science", we spent 3/4 of the year on Geometric Optics and 1/4 of the year on Kinematics & Dynamics. The main emphases of the course included experimental design, analysis of data (via graphical and mathematical models), and report writing.

When I returned to Clayton as a teacher in 1989, Quantitative Science was still in place for the honors kids and I spent two years teaching the "regular" freshman physical science course which was, at that point, about 3/4 physics topics and 1/4 earth science. While at Clayton, I worked with Rex, Craig, and Chuck, although I was not directly involved in teaching any of the students during the transition period to all physics for all freshmen. (At that time I was teaching Chemistry to "regular" juniors who had completed the sequence of freshman physical science-sophomore biology.) I have shared the recent postings and interviews with a colleague who was involved in the curriculum inversion process and I believe you will find her insight as interesting as that of the others from CHS. Her account follows:

FROM ANOTHER FORMER CHEMISTRY TEACHER AT CLAYTON HIGH SCHOOL (anonymous):

I read your interviews with Chuck Collis and Craig Sucher from Clayton High School on the LISTSERV. I taught at Clayton High School for four years (Chemistry, Honors Chemistry, and Biochemistry) and was department co-chair with Rex Rice. I now teach at Ladue High School. Ladue and Clayton are considered to be among the top public high schools in Missouri. While I too prefer the physics-chemistry-biology sequence, I feel the need to clarify some points raised in your interviews.

When I first came to Clayton, the sequence was physics-biology-chemistry for non-honors students and physics-chemistry-biology for the honors students. The non-honors biology teachers were becoming frustrated with how much of their time was spent teaching basic chemical concepts such as bonding. This was not such a problem when biology was more descriptive and less molecular. However, with all the emphasis on molecular and cellular biology today, the need to teach some chemistry in biology classes became necessary. As a department, we explored many avenues to rectify this problem. In the end, we decided to change the sequence to chemistry BEFORE biology so as to best serve all our students. Craig Sucher and I were chosen to pilot the program. I taught the chemistry and Craig taught the biology. After a two year sequence (half the students were taught biology first and the other half chemistry first and then switched for the next year), there was very clear cut evidence from our student data that taking chemistry before biology was advantageous. The students had a better understanding of the molecular and cellular concepts, and the teacher was able to cover more biological concepts than previously. In contrast, most students did not seem to benefit from having biology before chemistry. Only those students who were deficient in math benefited because they had acquired more math skills before they took chemistry. So, the important point that was not emphasized in either interview was that chemistry should be taught before biology.

I do believe in teaching physics at the freshman level. I think the concepts and labs are ones that students can complete and master. However, to me the important points are (1) that biology should come after chemistry, and (2) success in high school chemistry demands maturity and skills atypical of the majority of ninth graders. If one accepts these two premises, then physics should definitely come before chemistry and then biology.

As to physics being a benefit to the chemistry class, it depends on the topics covered. When I was at Clayton, no electricity or electrostatics topics were covered with the honors students. As a result, I saw little difference in the achievement in chemistry from the students coming from w physics or biology first. Now, however, Clayton freshman teachers are introducing more of these topics which I believe will benefit the chemistry student.Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê Ê

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