PRESENTATION ON 2-CYCLE ORG CHEM by jizhen1947

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									 Effectiveness of a
  2-Cycle Organic
Chemistry Sequence
     Doug Schirch



                    BCCE, August 2010
      2-Cycle Organic Chemistry
• Covers material from a standard 2-semester
  course in a different sequence:
  – First semester: Survey course of the fundamentals
    of organic chemistry (functional groups,
    nomenclature, major reactions, etc.)
  – Second semester: Builds on top of the first
    semester, more in-depth coverage, more
    rigorous.
Problems with Standard Sequence
• 1-semester students (Biology and
  Environmental Science majors; 40%)
  – Miss many functional groups common in nature
    (carboxylic acids, amides, esters, amines, etc.)
  – Forced to learn less relevant material
• All students: often can’t see the forest for the
  trees.
• Small schools can’t offer separate courses
         With 2-Cycle Sequence
• 1-semester students:
  – Get a survey of the most pertinent organic
    chemistry.
• 2-semester students (Chem. majors and pre-
  professionals) :
  – Build a solid foundation in basic organic chemistry
    before engaging more advanced material.
  – In 2nd semester, forced to recall 1st semester
    material to build on it, resulting in better learning.
                   Outline
1. Background
2. Course content in each semester
3. My experiences
4. Results of standardized final exams before
   and after adopting a 2-cycle approach
5. Student opinions.
                   Background
• Previous publications:
  – Minter and Reinecke. J of Chem Ed. (1985), Vol. 62
     • At Texas Christian Univ.
  – Sartoris. J of Chem Ed. (1992), Vol. 69
     • At Wittenberg Univ.
  – Gravert. J of Chem Ed. (2006), Vol. 83
     • At St. Mary’s University of Minnesota
• All 3 reported higher ACS scores after
  adopting 2-cycle approach
• Material covered in 1st and 2nd semesters …
• Textbook options
  – 1st: Survey text, then 2nd: 2-semester text
  – 2-semester text used both semesters
  – [Interested in a text for 2-cycle approach?]
• Number of schools using this approach?
                           Sequence I Use
1st Semester                                 2nd Semester
Review of bonding theories, EN, etc.
Const. and geometric isomers,
conformers, intro to chirality

Intro. to all the major functional groups,
their nomenclature, and properties

Fundamental reactions for each functional
group

Limited mechanisms
Some multi-step synthesis problems
Lab: Standard purification techniques,
TLC, melting points, a synthesis, GC-MS
                           Sequence I Use
1st Semester                                 2nd Semester
Review of bonding theories, EN, etc.         Additional reactions
Const. and geometric isomers,                Additional mechanisms
conformers, intro to chirality

Intro. to all the major functional groups,   More depth on nucleophilic substitution
their nomenclature, and properties           and chirality

Fundamental reactions for each functional More complex multi-step synthesis
group                                     problems

Limited mechanisms                           Spectroscopy
Some multi-step synthesis problems
Lab: Standard purification techniques,       Lab: Syntheses, literature project,
TLC, melting points, a synthesis, GC-MS      qualitative analysis using MS, FT-NMR, FT-
                                             IR
            My experiences:
        what worked, what didn’t
• Textbook: 2-semester Carey for both
  semesters
• Homework:
  – Submitted more frequently, but
  – Insufficient problems in 1st semester sometimes
• In 2nd semester students are stronger, better
  prepared, and have better study skills
• Weekly help sessions no longer needed
• Problematic for transfers (?)
Comparison of Scores on Standardized Final
      Exam at End of 2nd Semester




                  Standard   2-cycle sequence
                  sequence
Comparison of Scores on Standardized Final
      Exam at End of 2nd Semester




                  Standard   2-cycle sequence
                  sequence
   Survey of Student Perceptions
• Survey sent to all previous students from the
  years a 2-cycle sequence used.

  – Of 31 one-semester students, 17 (55%)
    responded

  – Of 49 two-semester students, 30 (61%)
    responded
• “I think it was good to have the first semester of the
  course be a general survey of organic chemistry that
  covers the fundamental topics relevant to biology.”
                      1-semester         2-semester
                       students           students
Strongly Disagree     1       6%         0
Disagree              0                  0
Neither agree nor     0                  2       7%
disagree

Agree                 6      35%         15      50%
Strongly Agree       10      59%         13      43%
• “I found it confusing to be skipping some chapters or
  sections in the textbook.”


                     1-semester         2-semester
                      students           students
Strongly Disagree    3       18%        7      23%
Disagree             11      65%        18     60%
Neither agree nor    2       12%        3      10%
disagree

Agree                1       6%         2       7%
Strongly Agree       0                  0
• “I think it would be better to follow the standard
  sequence, going through the first half of the text in
  the first semester and the second half of the text in
  the second semester..”

                      1-semester         2-semester
                       students           students
Strongly Disagree     3      18%         8       27%
Disagree             11      65%         15      50%
Neither agree nor     2      12%         7       23%
disagree

Agree                 1       6%         0
Strongly Agree        0                  0
• “For the content we covered in the first semester, I
  think I would have learned better with a smaller
  textbook designed for a 1-semester introduction to
  organic chemistry course, instead of the larger 2-
  semester text that we used parts of.”
                     1-semester
                      students
Strongly Disagree    1       6%
Disagree             7       41%
Neither agree nor    6       35%
disagree

Agree                3       18%
Strongly Agree       0
• “Instead of the large 2-semester text that we used for both
  semesters, I think I would have learned better with a smaller
  textbook designed for a 1-semester introduction to organic
  chemistry course in the first semester, and then only using
  the larger 2-semester text for the second semester.”
                                               2-semester
                                                students
Strongly Disagree                              5       17%
Disagree                                      11       37%
Neither agree nor                              7       23%
disagree

Agree                                          7       23%
Strongly Agree                                 0
• “Seeing some material twice during the year (at an
  introductory level in the first semester and in more
  depth during the second semester) helped me learn
  the material better by the end of the course.”

                                        2-semester
                                         students
Strongly Disagree                       0       0%
Disagree                                1       3%
Neither agree nor                       1       3%
disagree

Agree                                   12     40%
Strongly Agree                          16     53%
                  Summary
• 2-cycle sequence allows a much better
  experience for 1-semester students
• 2-semester students show increased learning
  and prefer the 2-cycle approach
• The most significant problems (lack of specific
  text and transfer students) are minor

          For copy of PowerPoint or more info:
                         dougms@goshen.edu
Questions??

								
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