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Individualized instruction of biochemistry at Cornell University. A summary of experience after ten semesters
78
BIOCHEMICAL EDUCATION
October 1978
Voi. 6
No. 4
INDIVIDUALIZED INSTRUCTION OF JOSEPH CALVO
BIOCHEMISTRY AT CORNELL UNIVERSITY. A S U M M A R Y OF
M o l e c u l a r a n d Cell Biology Dlvlslon of Biological Science Cornell U m v e r s l t y Ithlca, New Y o r k , 14853, U S A
EXPERIENCE AFTER TEN SEMESTERS
Having a long-standing interest in the problems associated with large classes and being dissatisfied with what l perceived to be the inadequacies of the lecture format, I decided in 1971 to search for an alternative teaching strategy A sabbatic opportunity and some conversations w,th Joe Novak led me to Purdue University where, with Sam Postlethwaite, I explored an autotutorial approach to teaching biochemistry The outcome of that venture, modified considerably from the usual autotutorlal format, is Principles of Biochemistry, Individualized Instruction (Blo Sci 330), taught at Cornell for the past ten semesters
A Case History: The mechanics of the course can be conveniently illustrated by Table I and by following the progress of an undergraduate, Jeff Snedeker, as he made his way through the course m the fall term, 1976 Jeff learned basic facts and concepts from readmg Lehninger's "Biochemistry" in conjunction with a set of objectives and notes that we provided If he needed help with his work, it was available during the day and some evenings at a study center on the second floor of Stimson Hall The objectives were divided into 12 units of work, after completing each unit, he took a short oral examination that was judged as either satisfactory or unsatisfactory After flmshmg all 12 units, Jeff had passed the course and was assured a grade of at least C Because he was interested in going beyond the basic objectives, Jeff participated in a number of optional activities throughout the semester On eight occasions, he met with a group of other students and an instructor to discuss papers from the original literature that he had read (on metabolism and on genetic engineering) Two other hines he met with an instructor on a one-to-one basis and discussed a group of related papers he found of interest He chose two packets, one on Cancer and one on Membranes He worked independently at solving a variety of quantitative problems When he was ready, his work was evaluated at the study center, again, by an oral examination With this elective work successfully completed and evaluated (grade C~B), Jeff began to study for the comprehensive final examination The latter, required of all students, was designed primarily with the intention of identifying students having aptitude for biochemistry Jeff's score was above average, a prerequisite for a course grade higher than B His fmal grade was A Because he did so well on the final, and because the staff felt that he would interact well with his peers, Jeff was invited to serve as an undergraduate teaching assistant the next term Table I Activities that Replace Lectures in Bio Sci 330
Activity
Evaluation
Contmbutlon to Grade*
Core material (organized as 12 units)
oral
C
oral
C+, B - B*
written
B+, A - , A, A+*
Elective work Discussion groups Readlngpackets Quantitative problems Final exam
*Actual grade depends upon quality and quantity of work done
How Students View the Course: The results of questionnaires indicated that students viewed this course as being taught at an appropriate level, although they didn't consider it inherently difficult, they felt the course required considerable independent thought (Table II) Clearly, we do not overtax the abilities of our undergraduates when we ask them to dig material out of books or to read original scientific research papers Students reported that they invested a great deal of effort in the course (Table II) On several occasions, we kept accurate records of the time students said they spent studying for each of the activities listed in Table I The average total effort (160 hours for the semester, about equally divided between core and elective work) was about equal to what students would invest in a 4 credit-hour lecture course if they studied two hours for each hour spent in lecture Table II Student Evaluation of Bto Sci 330 % students selecting chol~.e~ Question
S
4
3
2
1
1
Was the course taught at an appropriate level~ (S = overestimated ability)
1
23
69
5
2
2
Difficulty (5 = much harder than most)
13
40
41
5
l
3
Independent thought required9 (S = thinkang always required)
34
42
17
6
1
4
Effort invested in the course (5 = much more than for most courses)
45
37
16
1
1
5
Did staff stimulate interest in sublect~ (5 - greatly stimulated interest)
26
47
21
4
5
6
Overallimpression of course (5 = excellent course)
41
41
13
3
2
*Numbers are averages from last three spring terms with about 100 students responsmg each term One of the major advantages of the lecture format is that by bringqng their own unique knowledge and perspective to bear, skilled lecturers can "turn on" students to their dlsctphnes This aspect of teachmg is more difficult to achieve with an auto-tutorial format because students' expermnces are likely to vary widely, depending upon which activities they choose and which teaching assistants and instructors they come in contact with While our experience with auto-tutorials might not be equivalent to an exceptional lecturer in this respect, it certainly came out respectably in terms of the question, "Did the staff stimulate your interest in the subject 'r' (Table II) More than half of the students (52°7o) noted that AT biochemistry compared favorably with an excellent lecture course and another 40 per cent judged that tt compared favorably with a good lecture course It is important to note that this favorable reaction is not dependent upon one particular personality Over the past 10 semesters, 3 different professors have been in charge and some 23 instructors and 44 undergraduate TA's have been involved with the course
BIOCHEMICAL EDUCATION
October 1978
What Students Learn in Such a Counrse:
Our staff requirements are certainly larger t h a n what is usual for a typical lecture course This m u s t be the case for any courses attempting to mdlvtduahze instruction However, the size of the staff may not be disproportionate when viewed m another context Some biochemistry departments teach three or four beginning biochemistry courses, each aimed at a different group of students (biochemistry majors, Ag students, biology students, etc ) We have chosen isstead to offer just two levels of biochemistry, one for students lacking organic chemistry as a prerequisite (BS 231), and the other for students having this prerequisite (BS 330, 331) Between the auto-tutorial course (BS 330) and the lecture course (BS 331), we are able tn accommodate students with a wide range of interests Furthermore, the TA experience that we offer our best students is equivalent to a second semester of biochemistry, something avadable to most majors at other universities T h u s , the total staff that we mobilize to teach about 800 undergraduate students may not be m u c h different from that at comparable restitutions
Jeff's experience with AT biochemistry (oral exams on 12 units of core material, discussions of research papers, independent reading, quantitative problem solving, comprehensive h n a l exam) can be contrasted with a typical experience with a 4 credit-hour lecture course In the one attempt that we made to assess this question, we administered a standardized national test as a final exam Compared with national norms, a slgmflcanfly lower proportion of our students scored very low on the exam (Fig 1) On the other hand, a somewhat lower proportion of our students received marks higher than the national n o r m Personally, I f m d it dtffmult to compare the lecture and AT expermnces I suspect that how m u c h a student learns and retains is primarily dependent upon motivation and aptitude and only secondarily upon the particular orgamzation of a course I would like to think that Jeff received a n u m b e r of real (but not easily measured) benefits from AT biochemistry I would include a m o n g these (1) mcreased maturity, derived from a persistent requirement to dig information out of books, (2) appreciation for why and how bmchemists perform experiments (from reading research papers) and (3) a more h u m a n experience, originating from daily one-on-one interaction with peers and Instructors
Staff Necessary for Teaching Such a Course: For a group of 150 students, we require about a dozen undergraduate TA's and 6 instructors The undergraduate TA's perform a good share of the instruction because they do m u c h of the core material evafuatlon (recall that each student takes 12 oral examinations) Undergraduate TA's receive 3 hours of credit during their first teaching experience and are paid during subsequent semesters (about half are paid each semester) I am convinced that the involvement of undergraduate TA's is one of the best features of this course, both because of the individual attention it makes possible and the opportunity it affords our best students to teach Many will ask, " C a n someone with such hmited expermnce perform adequately as a teacher 9'' I believe that our undergraduate TA's are effective because they were selected for their demonstrated ability and because their responsibihtms were carefully chosen and delineated For example, they quiz students on basic facts and concepts that they themselves mastered On the other hand, they do not analyze research papers in discussion groups, something that requires a good deal of research experience A large majority of the students judged undergraduate TA's to be fair and impartial and in&cared that they did a good job On the other hand, only a few students (3%) felt that our TA's did not know enough biochemistry to administer exams on core material It is interesting that about half of the students indicated no preference between instructors and undergraduate TA's for administering oral examinations A m o n g those indicating a preference, half preferred instructors and half preferred undergraduate TA's The six instructors are chosen from faculty and graduate students, the major qualification being sufficient experience to discuss research One of the instructors, Martha Ferger, serves on a full-time basis, providing the contmmty and coordination necessary for the smooth functioning of the course
Concepts in Biochemistry - - Second Edition By W l l h a r n K S t e p h e n s o n P p 152 J o h n W i l e y a n d S o n s , New Y o r k 1978 P a p e r b a c k , £5 20 This self-lustl~ctton textbook xs designed to cover chemistry and biochemistry for a first year course in contemporary college biology and is particularly intended for those biology students with neither previous chemistry nor biochemistry The hrst third of the hook deals with covalent and ionic bonds, equdlbrlum, pH and the like and the rest of the book is largely an introduction to the structures of some biological molecules There is no metabolism mentioned and the carbohydrate chaptees ignore all phosphate derivatives of sugars although the structures of chitin and N-acetylneurammlc acids are given, so one does wonder about choice of priorities One
Vol. 6
No. 4
79
In Conclusions: I started out with the intention of devising a teaching strategy through which large n u m b e r s of students could be taught more effectively During this six-year experiment, however, I have developed a different perspecUve, namely, that while it currently may not be possible to devise a simple strategy to increase students' learning (as measured by conventional tests), tt is possible to orgamze a large course in a way that emphasizes other aspects of education These other aspects, which include fostering academm maturity and stimulating an interest and understanding of the process of science, are less tangible than transmitting factual knowledge but perhaps equally smportant
A X ¢0
.l= O" t-
,o-
203o0
u 40" N
g soJE
6o70"
eal
80-
. , ~ / B i o
SCl
330
~ 9oQ. I
I0 Figure 1
1
20
I
I
30 40 Score (x)
I
50
I
60
70
Scores on a standardized exam admimstered fall 1978
might think that the concept of enzymic action was central m biochemistry, yet enzymes get only four pages at the end a n d most of these are concerned with A T P Some of the questions are not very demanding - - e g " A s s u m e that the total A T P + A D P of a cell is 10,000,000 molecules If the A D P pool is 2,000,000, what is the A T P pool~" One novel feature is a strtp diagram of an alpha-hehx to be cut out W h e n coded up correctly, the NH and CO come together Hydrogen bonding is one of the concepts developed The book would seem to be satisfactory for the non-chemical biologist at a pre-unlversRy level who wants to get, m the 6 - 2 2 hours required to work through the book, some feel for biochemical structures and language but he should not delude htmself that he IS now competent in real biochemistry. B A Kdby
BIOCHEMICAL EDUCATION
October 1978
Voi. 6
No. 4
INDIVIDUALIZED INSTRUCTION OF JOSEPH CALVO
BIOCHEMISTRY AT CORNELL UNIVERSITY. A S U M M A R Y OF
M o l e c u l a r a n d Cell Biology Dlvlslon of Biological Science Cornell U m v e r s l t y Ithlca, New Y o r k , 14853, U S A
EXPERIENCE AFTER TEN SEMESTERS
Having a long-standing interest in the problems associated with large classes and being dissatisfied with what l perceived to be the inadequacies of the lecture format, I decided in 1971 to search for an alternative teaching strategy A sabbatic opportunity and some conversations w,th Joe Novak led me to Purdue University where, with Sam Postlethwaite, I explored an autotutorial approach to teaching biochemistry The outcome of that venture, modified considerably from the usual autotutorlal format, is Principles of Biochemistry, Individualized Instruction (Blo Sci 330), taught at Cornell for the past ten semesters
A Case History: The mechanics of the course can be conveniently illustrated by Table I and by following the progress of an undergraduate, Jeff Snedeker, as he made his way through the course m the fall term, 1976 Jeff learned basic facts and concepts from readmg Lehninger's "Biochemistry" in conjunction with a set of objectives and notes that we provided If he needed help with his work, it was available during the day and some evenings at a study center on the second floor of Stimson Hall The objectives were divided into 12 units of work, after completing each unit, he took a short oral examination that was judged as either satisfactory or unsatisfactory After flmshmg all 12 units, Jeff had passed the course and was assured a grade of at least C Because he was interested in going beyond the basic objectives, Jeff participated in a number of optional activities throughout the semester On eight occasions, he met with a group of other students and an instructor to discuss papers from the original literature that he had read (on metabolism and on genetic engineering) Two other hines he met with an instructor on a one-to-one basis and discussed a group of related papers he found of interest He chose two packets, one on Cancer and one on Membranes He worked independently at solving a variety of quantitative problems When he was ready, his work was evaluated at the study center, again, by an oral examination With this elective work successfully completed and evaluated (grade C~B), Jeff began to study for the comprehensive final examination The latter, required of all students, was designed primarily with the intention of identifying students having aptitude for biochemistry Jeff's score was above average, a prerequisite for a course grade higher than B His fmal grade was A Because he did so well on the final, and because the staff felt that he would interact well with his peers, Jeff was invited to serve as an undergraduate teaching assistant the next term Table I Activities that Replace Lectures in Bio Sci 330
Activity
Evaluation
Contmbutlon to Grade*
Core material (organized as 12 units)
oral
C
oral
C+, B - B*
written
B+, A - , A, A+*
Elective work Discussion groups Readlngpackets Quantitative problems Final exam
*Actual grade depends upon quality and quantity of work done
How Students View the Course: The results of questionnaires indicated that students viewed this course as being taught at an appropriate level, although they didn't consider it inherently difficult, they felt the course required considerable independent thought (Table II) Clearly, we do not overtax the abilities of our undergraduates when we ask them to dig material out of books or to read original scientific research papers Students reported that they invested a great deal of effort in the course (Table II) On several occasions, we kept accurate records of the time students said they spent studying for each of the activities listed in Table I The average total effort (160 hours for the semester, about equally divided between core and elective work) was about equal to what students would invest in a 4 credit-hour lecture course if they studied two hours for each hour spent in lecture Table II Student Evaluation of Bto Sci 330 % students selecting chol~.e~ Question
S
4
3
2
1
1
Was the course taught at an appropriate level~ (S = overestimated ability)
1
23
69
5
2
2
Difficulty (5 = much harder than most)
13
40
41
5
l
3
Independent thought required9 (S = thinkang always required)
34
42
17
6
1
4
Effort invested in the course (5 = much more than for most courses)
45
37
16
1
1
5
Did staff stimulate interest in sublect~ (5 - greatly stimulated interest)
26
47
21
4
5
6
Overallimpression of course (5 = excellent course)
41
41
13
3
2
*Numbers are averages from last three spring terms with about 100 students responsmg each term One of the major advantages of the lecture format is that by bringqng their own unique knowledge and perspective to bear, skilled lecturers can "turn on" students to their dlsctphnes This aspect of teachmg is more difficult to achieve with an auto-tutorial format because students' expermnces are likely to vary widely, depending upon which activities they choose and which teaching assistants and instructors they come in contact with While our experience with auto-tutorials might not be equivalent to an exceptional lecturer in this respect, it certainly came out respectably in terms of the question, "Did the staff stimulate your interest in the subject 'r' (Table II) More than half of the students (52°7o) noted that AT biochemistry compared favorably with an excellent lecture course and another 40 per cent judged that tt compared favorably with a good lecture course It is important to note that this favorable reaction is not dependent upon one particular personality Over the past 10 semesters, 3 different professors have been in charge and some 23 instructors and 44 undergraduate TA's have been involved with the course
BIOCHEMICAL EDUCATION
October 1978
What Students Learn in Such a Counrse:
Our staff requirements are certainly larger t h a n what is usual for a typical lecture course This m u s t be the case for any courses attempting to mdlvtduahze instruction However, the size of the staff may not be disproportionate when viewed m another context Some biochemistry departments teach three or four beginning biochemistry courses, each aimed at a different group of students (biochemistry majors, Ag students, biology students, etc ) We have chosen isstead to offer just two levels of biochemistry, one for students lacking organic chemistry as a prerequisite (BS 231), and the other for students having this prerequisite (BS 330, 331) Between the auto-tutorial course (BS 330) and the lecture course (BS 331), we are able tn accommodate students with a wide range of interests Furthermore, the TA experience that we offer our best students is equivalent to a second semester of biochemistry, something avadable to most majors at other universities T h u s , the total staff that we mobilize to teach about 800 undergraduate students may not be m u c h different from that at comparable restitutions
Jeff's experience with AT biochemistry (oral exams on 12 units of core material, discussions of research papers, independent reading, quantitative problem solving, comprehensive h n a l exam) can be contrasted with a typical experience with a 4 credit-hour lecture course In the one attempt that we made to assess this question, we administered a standardized national test as a final exam Compared with national norms, a slgmflcanfly lower proportion of our students scored very low on the exam (Fig 1) On the other hand, a somewhat lower proportion of our students received marks higher than the national n o r m Personally, I f m d it dtffmult to compare the lecture and AT expermnces I suspect that how m u c h a student learns and retains is primarily dependent upon motivation and aptitude and only secondarily upon the particular orgamzation of a course I would like to think that Jeff received a n u m b e r of real (but not easily measured) benefits from AT biochemistry I would include a m o n g these (1) mcreased maturity, derived from a persistent requirement to dig information out of books, (2) appreciation for why and how bmchemists perform experiments (from reading research papers) and (3) a more h u m a n experience, originating from daily one-on-one interaction with peers and Instructors
Staff Necessary for Teaching Such a Course: For a group of 150 students, we require about a dozen undergraduate TA's and 6 instructors The undergraduate TA's perform a good share of the instruction because they do m u c h of the core material evafuatlon (recall that each student takes 12 oral examinations) Undergraduate TA's receive 3 hours of credit during their first teaching experience and are paid during subsequent semesters (about half are paid each semester) I am convinced that the involvement of undergraduate TA's is one of the best features of this course, both because of the individual attention it makes possible and the opportunity it affords our best students to teach Many will ask, " C a n someone with such hmited expermnce perform adequately as a teacher 9'' I believe that our undergraduate TA's are effective because they were selected for their demonstrated ability and because their responsibihtms were carefully chosen and delineated For example, they quiz students on basic facts and concepts that they themselves mastered On the other hand, they do not analyze research papers in discussion groups, something that requires a good deal of research experience A large majority of the students judged undergraduate TA's to be fair and impartial and in&cared that they did a good job On the other hand, only a few students (3%) felt that our TA's did not know enough biochemistry to administer exams on core material It is interesting that about half of the students indicated no preference between instructors and undergraduate TA's for administering oral examinations A m o n g those indicating a preference, half preferred instructors and half preferred undergraduate TA's The six instructors are chosen from faculty and graduate students, the major qualification being sufficient experience to discuss research One of the instructors, Martha Ferger, serves on a full-time basis, providing the contmmty and coordination necessary for the smooth functioning of the course
Concepts in Biochemistry - - Second Edition By W l l h a r n K S t e p h e n s o n P p 152 J o h n W i l e y a n d S o n s , New Y o r k 1978 P a p e r b a c k , £5 20 This self-lustl~ctton textbook xs designed to cover chemistry and biochemistry for a first year course in contemporary college biology and is particularly intended for those biology students with neither previous chemistry nor biochemistry The hrst third of the hook deals with covalent and ionic bonds, equdlbrlum, pH and the like and the rest of the book is largely an introduction to the structures of some biological molecules There is no metabolism mentioned and the carbohydrate chaptees ignore all phosphate derivatives of sugars although the structures of chitin and N-acetylneurammlc acids are given, so one does wonder about choice of priorities One
Vol. 6
No. 4
79
In Conclusions: I started out with the intention of devising a teaching strategy through which large n u m b e r s of students could be taught more effectively During this six-year experiment, however, I have developed a different perspecUve, namely, that while it currently may not be possible to devise a simple strategy to increase students' learning (as measured by conventional tests), tt is possible to orgamze a large course in a way that emphasizes other aspects of education These other aspects, which include fostering academm maturity and stimulating an interest and understanding of the process of science, are less tangible than transmitting factual knowledge but perhaps equally smportant
A X ¢0
.l= O" t-
,o-
203o0
u 40" N
g soJE
6o70"
eal
80-
. , ~ / B i o
SCl
330
~ 9oQ. I
I0 Figure 1
1
20
I
I
30 40 Score (x)
I
50
I
60
70
Scores on a standardized exam admimstered fall 1978
might think that the concept of enzymic action was central m biochemistry, yet enzymes get only four pages at the end a n d most of these are concerned with A T P Some of the questions are not very demanding - - e g " A s s u m e that the total A T P + A D P of a cell is 10,000,000 molecules If the A D P pool is 2,000,000, what is the A T P pool~" One novel feature is a strtp diagram of an alpha-hehx to be cut out W h e n coded up correctly, the NH and CO come together Hydrogen bonding is one of the concepts developed The book would seem to be satisfactory for the non-chemical biologist at a pre-unlversRy level who wants to get, m the 6 - 2 2 hours required to work through the book, some feel for biochemical structures and language but he should not delude htmself that he IS now competent in real biochemistry. B A Kdby