Understanding Attrition in an Introductory Chemistry Sequence

Research: Science and Education edited by

Chemical Education Research

Diane M. Bunce The Catholic University of America Washington, DC 20064

Christopher F. Bauer Understanding Attrition University of New Hampshire Durham, NH 03824-3598 in an Introductory Chemistry Sequence Following Successful Completion of a Remedial Course

Kathy B. Jones and Gregory I. Gellene* Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 *[email protected]

For more than 75 years the chemical education literature has addressed the importance of assessing the preparation of students for a required chemistry curriculum and implementing a scheme for accommodating the wide variety of abilities of these students (1). Most of the effort has been devoted to developing and validating evaluation criteria (1–31), with considerably less attention devoted to assessing the value of various modes of remediation (12, 13, 16, 20, 32–34), some sort of which must be implemented if an evaluation procedure is to have practical meaning. Very recently (35), a study reported on the effectiveness of a chemistry placement examination (CPE) and the ensuing remediation course at Texas Tech University, which involved almost 6000 students over a six-year period: two remarkable and unexpected conclusions emerged. First, the results indicated that little or no special benefit is gained by the successful completion of the remedial course—in fact, unremediated–underprepared (uu) students, remediated– underprepared (ru) students, and prepared (p) students performed comparably in a first fundamental chemistry course. In particular, the final average percentage score of these three groups are statistically indistinguishable at the 95% confidence level, and only partially distinguishable at the 90% confidence level with the statistically significant differences being about one-half of a typical letter grade, and then only for students having SAT mathematics scores within the range of 510–700 (p versus uu), 460–600 (ru versus uu), or 560– 700 (p versus ru) (35). Looking beyond the final average scores to a qualitative examination of success (defined as a grade of A, B, or C) in the first fundamental chemistry course revealed the second major conclusion of the study. Because so many students did not continue in the chemistry curriculum following remediation, the fraction of the students successfully completing the first fundamental chemistry course actually decreased after the implementation of the CPE and remedial course program. This is the exact opposite of the intended effect. The most worrisome feature of this attrition is that 44% of students receiving a grade of A, B, or C in the remedial course (i.e., successful completion) did not continue in the Texas Tech University chemistry curriculum. Such attrition is not unknown with other institutions (13, 33, 34) reporting that 20–50% of qualified students that satisfactorily complete a remedial course do not continue. Unfortunately, those studies provided no insight into the cause of this attrition. Because a fundamental chemistry course is required for almost all science, engineering, and pre-medical field or health www.JCE.DivCHED.org

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care academic majors and programs, understanding the cause of this attrition represents an important challenge to university level chemistry educators. This paper takes the first step in that direction with the report of survey results from Texas Tech University students who successfully completed the remedial course between Fall 1999 and Fall 2002, but did not continue in the chemistry curriculum at Texas Tech. Chemistry Course Information The Texas Tech University catalog describes Chem 1301, Introductory Chemistry, this way: Basic vocabulary, concepts, and problem-solving skills required for Chem 1307 and 1308. This course has no laboratory and will not satisfy a laboratory science requirement.

The last part of the description emphasizes that this course serves only a preparatory function and satisfies no other academic degree or program requirement. Thus the choice to not continue past Chem 1301 to Chem 1307 represents a choice to abandon, at least temporarily, whatever one of the large number of academic majors or programs that require chemistry proficiency. Throughout the three years of this study, students were placed in Chem 1301 if they scored below 50% on a locally written, multiple choice CPE. During this time, the text for this course was Zumdahl’s Basic Chemistry (36). The 24 sections of Chem 1301 were taught by different instructors: five permanent faculty members taught 12 sections; four temporary faculty members taught the other 12 sections. While instructor variation is always a worry in comparisons of student performance, this concern is mitigated by the present emphasis on determining why successful students do not continue. Nevertheless, this issue can be objectively addressed by examining the survey results as a function of instructor. The Survey During May 2003, a mailing was sent to the permanent address on file for all students who completed Chem 1301 between the Fall 1999 and the Fall 2002 semesters with a grade of A, B, or C and did not enroll subsequently in Chem 1307 at Texas Tech University. The mailing contained a letter explaining the reason for the survey (i.e., to learn the cause for attrition of successful Chem 1301 students from the Texas Tech chemistry curriculum) and a postage-paid reply postcard listing possible reasons for not continuing in the Texas

Vol. 82 No. 8 August 2005

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Journal of Chemical Education

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Research: Science and Education

Tech chemistry curriculum. Students were asked to select one reason that best represented their own situation.

Percentage

80

Permanent (avg)

60

Temporary (avg) T4

40

1. I withdrew from the University.

20

2. I took Chem 1307 (or equivalent) at another university.

0

3. I never intended or needed to take Chem 1307 and was incorrectly advised to take Chem 1301.

R1

R2

R3

R4

R5

Yes

No

F

N

U

Responses Figure 1. Distribution of survey responses as a function of the temporary or permanent nature of the instructor’s position. See the description of the survey in the text for a full explanation of the response labels. Response distributions do not necessarily total to 100% because some surveys were only partially completed.

Percentage

If you selected (4) or (5), was your Chem 1301 experience an important factor in your decision?

1999–2000 2000–2001

60 40

2001–2002

䊐 Yes

20

䊐 No

0 R1

R2

R3

R4

R5

Yes

No

F

N

U

Overall, my experience with Chem 1301 as a preparatory course was

Responses

䊐 Favorable—the course provided good new information and/or a needed review

80

Percentage

5. When I took Chem 1301, my major and/or career ambition was decided and I needed to take Chem 1307. I subsequently chose a major that did not require Chem 1307.

These five responses will be referred to as R1 through R5, respectively. Two additional questions sought to gather more information about students’ decision making.

80

60

Fall

䊐 Neutral

40

Spring

䊐 Unfavorable—I learned little or no new information—A waste of time

20 0 R1

R2

R3

R4

R5

Yes

No

F

N

U

Responses Figure 2. Distribution of survey responses as a function of when Chem 1301 was taken in terms of academic years (top panel), and semester (bottom panel). See the description of the survey in the text for a full explanation of the response labels. Response distributions do not necessarily total to 100% because some surveys were only partially completed.

60

A B

40

C

20 0 R1

R2

R3

R4

R5

Yes

No

F

N

U

Responses Figure 3. Distribution of survey responses as a function of Chem 1301 grade received. See the description of the survey in the text for a full explanation of the response labels. Response distributions do not necessarily total to 100% because some surveys were only partially completed.

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Finally, the survey card provided a space for free response comments. Although individual circumstances can be highly variable, the menu portion of the survey was organized so that the first three responses represented attrition reasons that generally are not expected to be attributable to any particular aspect of the Chem 1301 experience, whereas, for the last two responses, such a linkage reasonably could be expected. Then, the first follow-up question explicitly probes this possible linkage and the second follow-up question allows the nature of the linkage to be characterized. It is worth noting that a student may sensibly indicate that the Chem 1301 experience influenced them in choosing or switching to a major that did not require Chem 1307 and report a favorable Chem 1301 experience. Results

80

Percentage

4. When I took Chem 1301, my major and/or career ambition was undecided and I thought I might need Chem 1307. I subsequently chose a major that did not require Chem 1307.


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From the original mailing of 819 surveys, 103 were returned to sender (RTS) for incorrect addresses and 156 response cards were received, representing 21.7% of the 716 surveys that, presumably, were delivered to former students. Forwarding addresses were provided for 60 of RTS and were utilized in a second mailing that yielded 12 additional response cards (20% response ratio). Each response card was coded, allowing responses to be correlated with instructor, semester taken, and grade received. The results are summarized in the bar graphs of Figures 1–3. In each graph, R1 through R5 denotes which one of the five reasons given for


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not continuing in the Texas Tech chemistry curriculum was selected, normalized to the total number of respondents. “Yes” and “No” denotes whether the Chem 1301 experience influenced the respondent’s decision, normalized to the number of respondents selecting R4 or R5. F, N, and U denotes whether the respondent labeled his or her overall Chem 1301 experience as favorable, neutral, or unfavorable, normalized to the total number of respondents. Because some surveys were only partially completed, the response distributions do not necessarily total to 100%.

Effect of Instructor as a Factor in Attrition Because some instructors taught as few as one section of Chem 1301, and only one instructor taught more than two sections during the three years of the study, with one exception, the number of responses received was not sufficient to allow a meaningful comparison of each individual instructor. The exception was one temporary instructor (denoted T4) who taught five of the seven sections of Chem 1301 offered during the 2001–2002 academic year. Although at the start of this study there was no reason to anticipate that the responses of T4 students would be atypical, it turned out that this instructor was particularly well-received by the students. Thus, because sufficient responses were received to allow an individual instructor analysis for T4, the results of this instructor will be highlighted to examine the effects of a particularly well-received instructor. More generally, however, by grouping responses by whether the instructor was a permanent or temporary faculty member, some useful comparisons can be made. The various instructor comparisons are summarized in Figure 1. A very similar response pattern is observed for permanent and temporary faculty instructors and T4 in the R1–R5 portion of the survey with “changed my major” (combined R4 and R5) accounting for at least 50% of the responses. The second most frequent response (13– 22%) was that “Chem 1307 was taken elsewhere” (R2) followed by “withdrew from the university” (R1) with a comparable frequency of response (11–17%). The least frequent response (3–6%) was “incorrectly advised to take Chem 1301” (R3). In response to the first follow-up question targeted at students who “changed their major” (R4 and R5), most respondents indicated that their Chem 1301 experience was not an important factor in their decision. This majority is slim (~6:5) for respondents taught by permanent faculty, and more significant (~3:2) for those taught by temporary faculty. However when the contribution from respondents taught by T4, for whom the majority was very substantial (~5:2), is removed from the temporary instructor average, the result for the remaining three temporary instructors (~1:1) is very comparable to the permanent instructor result. In response to the second follow-up question, regardless of instructor type, most respondents characterized their Chem 1301 experience as favorable, followed by neutral, with unfavorable being the least frequent response. Again, this plurality is slim for respondents taught by permanent instructors (~10:9:8), more significant for respondents taught by temporary instructors (~9:6:4), and quite substantial for respondents taught by T4 (~6:2:1). For this question, however, removing the contribution of T4 respondents from the temporary instructor average shifts the most frequent characterwww.JCE.DivCHED.org

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ization away from favorable, and toward neutral and unfavorable (~7:10:8).

Effect of Semester Timing as a Factor in Attrition The response ratio mostly increased as the time since Chem 1301 was taken decreased, with response percentages of 19.8, 18.2, 23.3, and 25.0 being observed for students taking the course in the 1999–2000, 2000–2001, 2001–2002 academic years, and the Fall 2002 semester, respectively. With a few exceptions, the responses show only a mild dependence on when the course was taken when the responses are grouped by academic year (top panel in Figure 2). Throughout the three-year time period, “changed my major” (R4 and R5) is consistently the most frequent response (47–63%) in the first part of the survey. However, the response to whether the Chem 1301 experience was an important factor in the decision to change majors did depend on when the course was taken. “Yes” was slightly favored in the 1999–2000 academic year (about 7:6) and “No” was somewhat more strongly favored in the 2000–2001 and 2001–2002 academic years (about 2:1 and 3:1, respectively). Consistently, the Chem 1301 experience was rated as “favorable” or “neutral” by at least a 3:2 margin with these responses exceeding “unfavorable” by more than a 6:1 margin in the 2001–2002 academic year. The somewhat anomalous response pattern for the 2001–2002 academic year can be traced to responses of the T4 students. In an alternative analysis of these data, grouping the responses by the semester in which students took Chem 1301 (Fall or Spring) revealed several interesting contrasts. For example, Spring respondents indicated that they took Chem 1307 at another university (R2) almost twice as frequently as did Fall respondents. Furthermore, although the combined R4 and R5 response frequency for the two semesters are comparable (Fall, 54.7% and Spring, 47.5%), Fall respondents were about one-third more likely than Spring respondents to have had a declared major (R5) when a major not requiring chemistry is selected instead. Remarkably, this decision was influenced by the Chem 1301 experience of Fall respondents more than 4 times as frequently as Spring respondents, whereas Spring respondents rated the course as favorable 50% more frequently than did Fall respondents. Effect of Final Grade as a Factor in Attrition Some interesting distinctions are observed when the responses are viewed as a function of the Chem 1301 course grade. Although “changed my major” (R4 and R5) still dominates the response to the first part of the survey (46–59%), A and B respondents were about twice as likely as C respondents to take Chem 1307 (or its equivalent) at another university (R2) and no A respondents reported withdrawing from the university (R1). The importance of the Chem 1301 experience in deciding to change majors was also grade dependent, with A respondents overwhelmingly (about 12:1) responding that it was not a factor while for B and C respondents the two responses are comparably represented. Overall, A and B respondents most frequently rated the Chem 1301 experience as favorable while C respondents rated it most frequently as neutral. However, regardless of grade received, an unfavorable rating was never given by more than 25% of the respondents.


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Discussion The results of the survey provide substantial insight into why about 44% of students who successfully completed a remedial chemistry course did not enroll in the subsequent chemistry course for which they had been preparing. Although some response variation (depending on the instructor, when the course was taken, or the grade received) was observed, several consistent, noteworthy trends are apparent. From an institutional point of view, it is gratifying that very few respondents (4.8% overall) reported being incorrectly advised to take Chem 1301 (R3), and from an educational perspective, it is encouraging to learn that 16.1% of the respondents did indeed continue in the chemistry curriculum, albeit at another university (R2). Combining these results with the 11.9% of the respondents who indicated that they withdrew from the university (R1), the survey indicates that about one-third (32.8% of the respondents) of the attrition was either not actual attrition (R2) or resulted from circumstances unrelated to the chemistry curriculum (R1 and R3). The most frequent responses (collectively 53.3% of the respondents)—independent of instructor, year and semester taken, or grade received—were that the student either chose (R4), or changed to (R5) a major that did not require Chem 1307. If the underlying cause for choosing a non-chemistry required major, and thus, in many cases, a new career goal, was a negative Chem 1301 experience, these responses would be cause for concern and possibly the motivation for curriculum reform. However, about one-third more of the R4 and R5 respondents indicated that the Chem 1301 experience did not influence their subsequent choice of a major not requiring chemistry than those who indicated it did influence them (32.5% yes, 43.8% no, 23.6% no response), and collectively, less than a quarter of the respondents rated their overall Chem 1301 experience as unfavorable. Furthermore, of the R4 and R5 respondents who did answer yes to the first follow-up question, 50% indicated either a favorable or neutral experience in the course. Taken together, therefore, the responses to the follow-up questions indicate that only about 8.6% of all respondents were influenced by an unfavorable Chem 1301 experience to chose a major which did not require chemistry. While this result indicates that the chemistry curriculum attrition might be lowered through a modification of the Chem 1301 content or presentation, substantial curriculum reform aimed at addressing this issue does not appear necessary. Combining the present results with those of the previous study (35), where the attrition was first identified and quantified, indicates that about 21% of successful Chem 1301 students with a declared major change their major to one not requiring chemistry (R5). This statistic can be put into context by comparison to the extent of declared major changing throughout the university. For new students entering Texas Tech University in the Fall 2002 semester with a declared science or engineering major, 23.5% declared a new major within one year. For all other declared majors, a comparable 24.7% changed their declared major within one year. Of course it is possible that some of the science or engineering declared major changes may have been from one science or engineering discipline to another, and thus represent a relatively minor career goal change; nevertheless, it appears that 1244


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successful Chem 1301 students may be changing their declared major less frequently, and certainly no more frequently, than either the general university population, or the smaller group of declared science and engineering majors. Although it would be interesting to know the detailed reasons why successful Chem 1301 students change their majors, the survey was not designed to address that question beyond determining whether the Chem 1301 experience was a major factor in the decision process. The survey results and the comparison with the general population indicate that curriculum reform in the preparatory course is unlikely to reduce attrition and is thus not warranted. Free response comments were included by approximately 60% of the respondents; respondents rating the course as unfavorable were more likely to include comments than respondents rating the course as neutral or favorable. In particular, 44 comments could be characterized as negative, 43 as neutral, and only 12 as positive. In several cases, a negative comment was paired with either a neutral (10% of the comments) or favorable (5% of the comments) overall rating. With one exception, the comments did not provide reasons for attrition beyond those offered in the first part of the survey. The exception involved two respondents who both indicated that they intend to take Chem 1307 in a future semester, but have delayed enrolling in the course because they would have fallen behind in the requirements of their particular program if they devoted two consecutive semesters to fulfilling their Chem 1307 requirement. Clearly, the remedial chemistry program is expected to be most effective when Chem 1301 and Chem 1307 are taken in consecutive semesters. If there are academic programs that make this difficult, some curriculum and scheduling accommodations may need to be considered. It is often conjectured that attrition in a major or program can be affected by how an instructor, particularly in an introductory course, is perceived by the students. The common prediction is that enrollment will be diminished by exposure to a poorly received instructor, and augmented by exposure by a well-received one. Although the first proposition cannot be addressed by the present results, some insight into the second proposition can be obtained by focusing on the responses for students of instructor T4, (i.e., a particularly well-received instructor). Contrary to conventional expectations, the frequency with which successful Chem 1301 respondents of instructor T4 did not continue in the TTU chemistry curriculum for whatever reason was found to be about 3% higher than the average of the rest of the instructors. However, when this statistic is adjusted for the finding that 18.8% of the T4 respondents continued their chemistry education at another university (R2) as compared to 15.1% of the alternate instructor respondents, the chemistry curriculum attrition difference between respondents of T4 and those of other instructors is less than 1%. Thus, in this case, being taught by a particularly well-received instructor does not appear to improve significantly the likelihood that the students would continue in the chemistry curriculum. Finally, possible explanations for the three significant Fall–Spring variations noted in the lower panel of Figure 2 can be offered. Considering first the increased frequency of Spring respondents to take Chem 1307 at another university, it seems reasonable that these students are more likely


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than Fall students to take Chem 1307 (or its equivalent) during the summer at universities or colleges located near their permanent residence. This scenario at least partially explains the (apparent) higher attrition in Spring versus Fall semesters that was first noted in the earlier study (35). The other two variations, Fall respondents being more frequently influenced by the Chem 1301 experience to change their major and Spring respondents more frequently giving Chem 1301 an overall favorable rating, may have a common origin. It is very often the case that Chem 1301 students are in their first year of university study and Chem 1301 is one of the more challenging subjects in their schedule. When this occurs in their very first semester. (i.e., 70.4% of Fall students; 46.2% of Spring students), while they are still transitioning from a high school teaching and learning environment, it would be natural, and even expected, to attribute academic difficulties to course instruction and content and be (perhaps overly) discouraged by their performance. On the other hand, once a realistic expectation of university style instruction has been gained (i.e., 53.8% of Spring students; 29.6% of Fall students), the students have the necessary perspective to properly evaluate the course and their own performance. On the whole, the results and observations of this study suggest that high attrition of successful remedial course students from the chemistry curriculum stems principally from a largely typical rate of major and career goal change and is not attributable to any particular aspect of the CPE and remedial course program. This conclusion, coupled with the marginal academic benefits of the remedial course determined in the previous study (35), suggests that institutions need to judge carefully whether a CPE-based required remediation in chemistry is worth the costs of institutional resources and academically delayed programs. Acknowledgments We are grateful for the financial support of the Camille and Henry Dreyfus Foundation through the Special Grants Program in the Chemical Sciences, and the Department of Chemistry and Biochemistry at Texas Tech University. We are also grateful to D. J. Casadonte, Jr. for his contributions to the development of the survey. The cooperation and support of the Institutional Research and Information Management office of Texas Tech University is also acknowledged.

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