LEARNING THEORY THROUGH VIDEOS

A Teaching Experience in a Theoretical Course based on Self-learning

Videos and Problem-solving Sessions

Marta Arias, Carles Creus, Adri

`

a Gasc

´

on and Guillem Godoy

Department of Llenguatges i Sistemes Inform

`

atics, Universitat Polit

`

ecnica de Catalunya, Jordi Girona 1-3, Barcelona, Spain

Keywords:

Self-learning, e-Learning, Videos, Teaching, Theory.

Abstract:

In this paper we describe a teaching experience applied to a theoretical course thought in a computer science

degree. The main feature of our experiment is the introduction of videos speciﬁcally designed for self-learning

as part of the learning process. Master classes are replaced by working sessions in which the involvement of

students gains prominence. The teacher explains almost nothing in class. Instead, most of the time is devoted

to the presentation of solutions to exercises assigned to students in advance. All presentations are done by

students, and the teacher only intervenes in order to complete explanations and correct mistakes.

The result of our experiment is promising from several perspectives. The exam results are better with the new

approach. The students learn to learn on their own and take better advantage of the time in class. The work

load is uniformly distributed along the course. The new approach also beneﬁts the teacher since he/she spends

considerably less time preparing theory lectures, and gets continuous feedback to better follow the students

developement.

The videos are valuable in themselves and have been made publicly available. In fact, our students prefer

them to a master class. They can pause, rewind and replay the video, take a rest, and postpone the lecture if

necessary. Moreover, the interest for these videos goes beyond our university boundaries: according to the

visits’ place of origin and posted comments, they are being used by students from other countries.

1 INTRODUCTION

Typically, lectures in mathematically founded sci-

ences include two different types of sessions: theory

and problems. The ﬁrst type often consists of a set of

lectures in which the professor presents all the basics

on the subject, such as deﬁnitions and proofs of rel-

evant and useful results. This kind of content is well

established and does not lend itself to discussion.

The second part is devoted to the presentation, ei-

ther by the teacher or students, of solutions to prob-

lems previously given as homework. This second part

is often understood as a practice for the exam.

In our experience, theory lectures impose a

rhythm which is often difﬁcult to follow by stu-

dents. Usually, theoretical concepts require an as-

similation time which exceeds the time allocated in

master classes, and it is different for every student.

Moreover, students tend to lose part of the teacher’s

explanation while taking notes. Their interaction with

the professor is limited to asking questions in case the

material is not well understood. In our opinion, the

teacher’s capabilities are not optimally exploited with

this kind of teaching approach, since active learning

approaches, and in particular problem-based learn-

ing, are especially well suited for scientiﬁc disciplines

(Handelsman et al., 2004). For this reason we believe

that active interaction in problem solving sessions

should be a central activity of the teaching process.

Educational theory suggests that there are better ways

to promote learning than the traditional master class

approach. The learning pyramid (see Figure 1), intro-

duced by the National Training Laboratories based on

Dale’s work (Dale, 1969), illustrates the average re-

tention of contents that corresponds to different teach-

ing methodologies, which is higher for audio-visual

material than for traditional lectures. In this vein, Tu-

tored Video Instruction (TVI, (Gibbons et al., 1977))

is a teaching method pioneered by Standford Univer-

sity. It consists in combining video-taped material

with teacher active tutoring. Our work falls into this

trend. The goal of this work is to combine video-

based material with problem-solving sessions where

the students actively present and discuss their solu-

93

Arias M., Creus C., Gascón A. and Godoy G..

LEARNING THEORY THROUGH VIDEOS - A Teaching Experience in a Theoretical Course based on Self-learning Videos and Problem-solving

Sessions.

DOI: 10.5220/0003333400930098

In Proceedings of the 3rd International Conference on Computer Supported Education (CSEDU-2011), pages 93-98

ISBN: 978-989-8425-50-8

Copyright

c

2011 SCITEPRESS (Science and Technology Publications, Lda.)

Figure 1: The Learning Pyramid.

tions.

In recent years, there has been a great increase in

the amount of audiovisual teaching resources freely

available on the Internet (VideoLectures, 2010; Aca-

demicEarth, 2010; KhanAcademy, 2010). On the

one side, one can ﬁnd commented slides and in-

formal explanations of a speciﬁc part of a sub-

ject (KhanAcademy, 2010). While this material is

well suited for solving particular questions when the

topic is already known, it is not enough for guiding

the learning process of a whole subject. On the other

side, one can ﬁnd recorded lectures given by special-

ists on a certain topic (VideoLectures, 2010; Aca-

demicEarth, 2010). They are usually very interesting

since they allow us to attend a master class taught by

an important professor regardless of time and place.

The main disadvantage of these videos is that their

content has no added value with respect to the origi-

nal class, and has all of its defects. For instance, they

may be disordered or redundant at times, and contain

mistakes derived from the difﬁculty of the subject and

improvisation. These mistakes cannot be easily ﬁxed

in the video.

For certain topics, teaching videos that are specif-

ically prepared for this purpose have several advan-

tages over regular master classes (Anderson et al.,

2001; Bauman and Jurgens, 2002; Day et al., 2005).

By careful preparation of content, image and audio,

one can produce a very succinct, well-ordered, ade-

quate and coherent material almost free of mistakes.

We have prepared videos of this kind for “Theory

of computation”, a course with a strong mathemat-

ical background of the computer science degree in

our University. These videos are intended as a self-

learning alternative to traditional master classes on

theory. Hence, they are self-contained, provide gen-

eral ideas, intuitions, precise deﬁnitions, proofs and

proposed exercises. The idea is to combine the pre-

cision and completeness of a textbook with the intu-

itions and dynamism of a good lecture.

Taking advantage of the videos, we have experi-

mented with the following teaching approach. Master

classes disappear and the teacher does not introduce

any material in class. Students learn theory on their

own by watching the videos, and are expected to solve

exercises assigned in advance. During class, students

explain their solutions on the blackboard as part of

the evaluation method. The teacher only intervenes in

order to complete explanations and correct mistakes.

One weekly session is devoted to study time, during

which students work on their own and the teacher is

present to help them, solving questions and giving in-

sights into the previously digested material. After this

continuous interaction with students, the teacher gets

a lot of feedback from each of them, making his/her

interventions more accurate and helping in the detec-

tion of common difﬁculties on the subject.

We applied our teaching approach to only one of

the groups of students of the course. The remain-

ing groups followed the traditional teaching method.

This allowed us to evaluate the impact of our method

versus the old one. The results are very promising:

students using the new approach were satisﬁed both

with the method and their performance on the sub-

ject. The professor that followed our method also ex-

pressed satisfaction with his new role in the course.

On the one hand, the method allowed him to inﬂu-

ence the students’ learning process more positively.

On the other hand, the teacher felt free from the te-

dious part of the lectures thus improving his general

attitude towards teaching the subject.

2 THE TEACHING EXPERIMENT

2.1 The Course

We have applied our teaching method to “Theory of

computation”, a mandatory course taught during the

second semester of the third year of our computer

science degree. This course is of theoretical nature,

and is heavily based on mathematic principles. The

objectives of this course are mainly twofold: ﬁrst,

to formally introduce the mathematical principles on

which computation is founded and, secondly, to teach

the students to follow and produce formal proofs and

solve problems in a rigorous manner. The contents

are hard, and students generally have difﬁculty with

the course. Moreover, it is mandatory, which alto-

gether results in a rather negative attitude towards the

subject. Despite the difﬁculty, the subject is interest-

ing, and the problems it presents can be very chal-

lenging and intriguing. This course has to compete

with other courses for the attention and dedication of

the students. These other courses tend assign more

applied work such as programming projects, which

are typically done in groups. Students spend a lot

of their time doing these projects, and concentrate on

CSEDU 2011 - 3rd International Conference on Computer Supported Education

94

this course just a week before the exam.

Students are divided into three groups, each taught

by a different professor. The lectures of two of the

groups are scheduled in the morning. The ones of the

third group are in the afternoon. We have applied our

new teaching methodology to the afternoon group but

allowing students to choose between the traditional

and the new evaluation method. The course has a

teaching load of three sessions of two hours each per

week (per group), the students are expected to devote

another 6 hours to self-study for an adequate assimi-

lation of the contents.

2.2 Comparison of Teaching

Approaches

The main difference between the traditional and

new methodologies is the use of especially designed

videos to teach the theoretical basis of the course con-

tents. Another difference is in the evaluation method.

In the new methodology, participation in the class-

room is explicitly considered in the grading method.

In our system, grades are between 0 and 10 (10 being

outstanding). A nominal qualiﬁcation is associated to

each mark range: 0 − 4.9 is failure, 5 − 6.9 is pass,

7 − 8.9 is good, 9 − 9.9 is excellent and 10 is with

honors. Students who fail (with a grade of less than

5) must take the course again. The results are usu-

ally not good. The percentage of students passing the

subject varies between 20% and 40%, resulting in a

high number of students taking this course 2 or even

3 times.

2.2.1 The Traditional Teaching Approach

In our university, “Theory of computation” is tradi-

tionally taught in a series of master classes. Two of

the three weekly sessions are devoted to the presen-

tation of theoretical contents by the professor. These

contents include deﬁnitions, fundamental results, and

formal proofs of the results. The third session consists

in solving problems where the concepts introduced in

the theory sessions have to be applied.

Lecturers usually encourage their students to par-

ticipate in class, with very little success. Partly, be-

cause participation is not explicitly considered in the

grading method. As a result, solutions are presented

by the teacher on the blackboard. For this reason,

problem solving lectures become in practice a mas-

ter class in which the students only copy the solutions

presented by the professor, with the hope of under-

standing this material while preparing for the ﬁnal

exam.

Evaluation Method. The students take ﬁve tests of

30 minutes each throughout the course. These tests

are fairly easy, since in order to pass them it is sufﬁ-

cient to carefully study some proofs given during the

theory lectures. Let C be the overall mark from all of

these tests, which is between 0 and 2.5. There is also

a ﬁnal exam, whose mark, F, lies between 0 and 10.

The mark of a student in this subject is obtained by

the formula F + (1 −

F

10

) ·C. The formula may seem

strange at ﬁrst. It is similar to a weighted average,

but note that the less F is, the more weight is given

to C. For example, if one gets a 10 in F (the best

grade possible), then the weight of C is 0. Thus, in

this case the value of C does not affect the ﬁnal mark.

If one gets a 0 in F (the worst grade possible), then the

weight of C is 1. Thus, in this case the ﬁnal mark is

just C. The formula beneﬁts students who work dur-

ing the course, even if they perform badly on the ﬁnal

exam. The following example illustrates this situa-

tion. If one gets a 4 in the ﬁnal exam (F), the weight

of C is 0.6. In this case, the ﬁnal grade is given by the

formula 4 + 0.6 ·C, which is between 4 and 5.5. So,

in this case, the student only passes if he/she obtains

a good grade on the tests (C).

2.2.2 The New Teaching Approach

We pretend to radically change the dynamics of lec-

tures, giving more emphasis to students’ involvement,

and making the professor’s role much more interac-

tive and fruitful.

Our new approach introduces both a different kind

of lecture and a new evaluation method. As men-

tioned above, students learn theory on their own by

watching the videos

1

, and the teacher does not intro-

duce any material in class. Instead, this time is used

by students to explain their solutions on the black-

board. Note that 4 hours of master classes are sub-

stituted in the new method by 4 hours of interactive

problem solving sessions. The third weekly session

is devoted to study time, during which the professor’s

only task is to solve and clarify questions. In other

words, the teacher is not grading or teaching, but is in

the class to help with the content. They can come with

their laptops, look at the videos again, ask questions

about them, and try to solve the assigned exercises

with possible hints given by the teacher. These ses-

sions create a positive atmosphere where the students

can more easily overcome their shyness and become

active members of the class.

1

Videos are posted on youtube and linked at the end of

the main subject’s page (www.lsi.upc.edu/˜ggodoy/tc.html).

LEARNING THEORY THROUGH VIDEOS - A Teaching Experience in a Theoretical Course based on Self-learning

Videos and Problem-solving Sessions

95

Evaluation Method. Given the nature of our insti-

tution and our students, participation does not come

easily. Therefore, we try to stimulate participation

by including it explicitly as part of the evaluation

method. To this end, the teacher scores presentations

of solutions by the students.

The new method has three parts: the results of

ﬁve tests taken during the course (C, the same ones

as in the traditional evaluation method), the result

of a ﬁnal exam (F, also present in the traditional

method) and a new part, P, corresponding to students

presentations of solutions to problems on the black-

board. The formula used to compute the ﬁnal grade is

min(10, 0.8·F + 0.6 ·C +P), where C ranges between

0 and 2.5, F ranges between 0 and 10, and P ranges

between 0 and 1.5. Note that with this methodology,

students can score a maximum of 11 points. This is to

encourage students to choose the new approach.

2.3 The Experiment

We have applied our new teaching methodology to the

afternoon group. The other two morning groups fol-

low the traditional approach. Our experiment consists

of comparing the performance of the students under

each of the methods applied. Note that the fact that

the new teaching approach is applied to the afternoon

group only, may be a drawback for the success of the

experiment: experience shows that the best students

are usually registered in the morning groups.

We believe that students should always have the

right to be evaluated with just a ﬁnal exam, there-

fore we allowed students in the experimental group

(i.e., the afternoon group), to choose between the tra-

ditional and the new evaluation method. That is, they

can attend the lectures with the new method, but they

will be scored with the traditional approach. Notice

also that all students have access to the videos, includ-

ing the ones in the morning groups. Moreover, any

student can beneﬁt from the problem solving sessions

and presentations by other students, even if he/she is

not required to do the presentations. Both these facts

may bias the result of the experiment against the new

method, since the newly created materials beneﬁt all

the students. It is also true that students of the af-

ternoon group could attend the master classes in the

morning. However, an opinion poll conducted among

students (see Section 3.2 below) indicates that stu-

dents prefer the videos to the master classes.

3 RESULTS

3.1 Video Accesses

The videos are posted on youtube

2

and are public.

This site monitors the number and origin of video

sightings. We give a brief summary of this data. We

restrict ourselves to the videos in catalan and span-

ish, since the ones translated to english have not been

available long enough to give meaningful numbers.

The number of accesses varies widely depending

on the video. As of October 21st, 2010, the most

viewed video has 5419 accesses. The least viewed

one has 126 accesses. In the following table, we count

the number of videos for several ranges of accesses.

Table 1: Video accesses.

# accesses # videos

125-249 20

250-499 6

500-999 7

≥1000 4

Only 27 students chose the new approach. From

their comments, we know that each of them watched

each video twice on average. It is expected that some

of the other students watched the videos too. How-

ever, most of the accesses come from other countries,

mainly from Latin America. Since the topic is the-

oretical and very speciﬁc, we believe that the view-

ers are students from other computer science degrees.

This fact suggests that the videos are useful to learn

the subject in general and not only in the context of

our teaching approach. Not surprisingly, the most ac-

cessed videos are the ones introducing classic mate-

rial that is present in any course in theory of compu-

tation.

3.2 Students’ Opinion

We collected anonymous opinions from students

along the course. Some of the students were taking

the subject for the second time, so that they were able

to compare both methods. Here we summarize the

most frequent ones:

• Being able to watch the video at one’s convenient

time is better than being forced to attend a lecture

at a ﬁxed time, thus avoiding situations when one

is tired after several classes, has had a plentiful

lunch recently, or has a bad day.

2

The videos are posted on the channel

http://www.youtube.com/guillemgodoy.

CSEDU 2011 - 3rd International Conference on Computer Supported Education

96

• With the videos, one can pause the lecture at any

time, take a rest, rewind it, and see it again and

again if necessary.

• With the old approach, once one gets lost in the

class, the rest of the time is useless. This problem

is solved with the new approach.

• Presenting solutions of problems each week is a

good motivation to follow the course. The mate-

rial is better understood in this way.

• The method forces one to work on the subject con-

tinuously during the course. The effort required is

constant during the course and not excessive. It

is deferential toward other subjects. The opposite

is not true in general. Other subjects have strong

peaks of work during the semester.

• A big amount of exercises are solved in class.

This makes it more interesting, and seems a better

preparation for the ﬁnal exam, which essentially

consists in solving exercises.

• The ﬁrst created videos are too slow. Neverthe-

less some students were able to accelerate them

making use of a computer application (the video

speaker is concerned about the quality and tone of

his/her voice as a consequence of such accelera-

tion).

3.3 Teachers’ Opinion

Here we summarize the impressions of the teacher

who applied the new method:

• The fact that the students have to present their so-

lutions on the blackboard motivates them much

more than just delivering a paper with the solu-

tion. In fact, being exposed to their classmates

criticisms forces them to prepare well their re-

spective presentations.

• The solutions presented by each student are very

interesting and rewarding for their classmates.

Even if such solutions contain mistakes, the dis-

cussion generated from them is very fruitful.

• The professor is more accessible to the students

with the new approach. They frequently ask ques-

tions about how to ﬁnd solutions and how to

present them.

• After an intensive interaction with the students

during the course, the professor has more accu-

rate information of each student, such as his/her

knowledge on the subject, skills, strengths and

weaknesses. Thus, it is possible to take more as-

pects into account in addition to the ones evalu-

ated by a written exam in order to give a ﬁnal mark

to each student.

• 1.5 points for the blackboard presentations are not

enough to motivate all students. Due to the high

workload imposed by other subjects, half of the

students did not solve the assigned exercises of

the last part of the course.

• The preparation time and effort of the teacher

is lower. It is not necessary to prepare master

classes, which is hard and takes time. The con-

tinuous evaluation is done in the class, so it does

not impose additional correction workload with

respect to the old approach.

3.4 Students’ Results

An unavoidable point for the comparison between the

previous and the new teaching approach is the per-

formance of students on the subject. We will avoid

ﬁne-grained comparisons since we consider that the

population is not large enough for a rigorous analysis.

Instead, we just present the result of our experience

letting the reader extract his/her own conclusions.

Table 2: Comparison of results.

Group 1 Group 2 Group 3

P N P N P N

# students 46 0 50 0 19 27

# students passing 12 0 20 0 7 20

% students passing 26.1% - 40.0% - 36.8% 74.1%

Table 2 shows the number of students registered

for the course, the number of students who passed the

course, and the percentage of this two values, grouped

by the followed teaching approach. In the table, P

stands for previous teaching approach, and N stands

for new teaching approach. Recall that only students

of group 3 were allowed to choose between the two

approaches while all the members of groups 1 and

2 were evaluated and taught using the previous ap-

proach.

Finally, we would like to remark that applying the

previous evaluation method to the 20 students that

passed the subject being evaluated with the new ap-

proach, 18 of them pass the subject anyway. In other

words, 18 students pass the subject with the old eval-

uation method out of the 27 students to which the

new teaching approach was applied. This represents a

66.7% of students passing the subject. This strongly

suggests that the good performance of students that

followed the new approach is not due to a more re-

laxed evaluation method.

LEARNING THEORY THROUGH VIDEOS - A Teaching Experience in a Theoretical Course based on Self-learning

Videos and Problem-solving Sessions

97

4 THE VIDEO CREATION

PROCESS

In this Section we describe the video creation process.

Each video is at most 10 minutes long, since this was

the limit given by youtube for freely submitted videos.

This length actually works ﬁne for us: a succinct and

well prepared video of 10 minutes may give as many

concepts as a class of 50 minutes, and it is more acces-

sible. This is because lectures are partly improvised,

the teacher can make mistakes, he/she can waste time

in complicated details which are difﬁcult to keep in

mind, may explain related facts which are interesting

but not central, etc.

We have created 37 videos in total, mostly in

Spanish.They are being currently translated to En-

glish. In fact, most of them have been already trans-

lated to English.

Our video creation method has evolved until ﬁnd-

ing a procedure with a good balance between qual-

ity and effort. The ﬁrst couple of videos took about

a week each to make. While they have been a suc-

cess in the sense that they have over 5000 visits and

positive comments, they took too much time to make.

After that, we thought of more efﬁcient ways to cre-

ate videos, and came up with the following process,

which we applied to all of the remaining videos.

1. First, we write a pdf document that contains the

image as well as the script of the video’s audio.

2. Secondly, we capture the audio. Any mistake is

immediately corrected by moving back the audio

recorder a few seconds.

3. Third, we mark a screen capture area and record

the image in this area while the audio is being

played.

4. Finally, we combine audio and video with a video

editor.

The second, third and fourth steps may require half

an hour in total for a video of 8 minutes. Hence, one

can invest most of the time in the ﬁrst step, namely

the creation of the contents.

In addition to a good balance between quality and

effort, our video creation approach has other advan-

tages: re-editing, correcting errors and translating into

other languages is very fast. One just needs to trans-

late image, script, and re-run the last steps (around 2

hours in total). Perhaps this method could be com-

bined with a pen tablet, a tablet pc or a smartboard of

enough quality to avoid the problems we mentioned

above.

5 CONCLUSIONS

We have tried a new teaching approach using spe-

cially designed videos for self-learning instead of

master classes. The results show that the method is

a success from different perspectives, such as exam

results, and students’ and teacher’s opinions. We be-

lieve that this method may also be useful for other

scientiﬁc matters.

Given the success of our videos in the Spanish-

speaking community, we recently translated

them to English to make their contents avail-

able to a wider audience. English version of

videos are posted on youtube and linked from

www.lsi.upc.edu/˜agascon/videostc. We are curious

to see what the impact of this translated material is.

We are also interested in sharing our experience with

other universities. In fact, we have made the videos

publicly available in order to beneﬁt the academic

community in general.

REFERENCES

AcademicEarth (2010). http://www.academicearth.org/.

Anderson, R., Dickey, M., and Perkins, H. (2001). Ex-

periences with tutored video instruction for introduc-

tory programming courses. ACM SIGCSE Bulletin,

33(1):347–351.

Bauman, E. and Jurgens, D. (2002). Undergraduate elec-

trical engineering via tutored video instruction. In

Frontiers in Education Conference, 1994. Twenty-

fourth Annual Conference. Proceedings, pages 460–

463. IEEE.

Dale, E. (1969). Audiovisual methods in teaching. Holt,

Rinehart and Winston, Inc., 383 Madison Avenue,

New York, NY 10017.

Day, J., Foley, J., Groeneweg, R., and van der Mast, C.

(2005). Enhancing the classroom learning experience

with web lectures. In Proceeding of the 2005 con-

ference on Towards Sustainable and Scalable Educa-

tional Innovations Informed by the Learning Sciences,

pages 642–645, Amsterdam, The Netherlands, The

Netherlands. IOS Press.

Gibbons, J. F., Kincheloe, W. R., and Down, K. S.

(1977). Tutored Videotape Instruction: A New

Use of Electronics Media in Education. Science,

195(4283):1139–1146.

Handelsman, J., Ebert-May, D., Beichner, R., Bruns, P.,

Chang, A., DeHaan, R., Gentile, J., Lauffer, S.,

Stewart, J., Tilghman, S. M., and Wood, W. B.

(2004). EDUCATION: Scientiﬁc Teaching. Science,

304(5670):521–522.

KhanAcademy (2010). http://www.khanacademy.org/.

VideoLectures (2010). http://www.videolectures.net/.

CSEDU 2011 - 3rd International Conference on Computer Supported Education

98