Pedagogical Principles for Evaluation of Hypermedia-Based Learning
Environments in Mathematics
Heli Ruokamo
(Tampere University of Technology, Finland
Heli.Ruokamo@cc.tut.fi)
Seppo Pohjolainen
(Tampere University of Technology, Finland
Seppo.Pohjolainen@cc.tut.fi)
Abstract: This paper discusses evaluation of hypermedia-based
learning environments mainly from the point of view of the learner or student.
The evaluation of a learning environment should be based on modern learning
theories. These emphasise the importance of constructivism and the learner's
activity in building mental models of the mathematical knowledge. The environment
should also support conversational and collaborative learning. From the
point of view of the learner it should be intentional and provide real
life situations and contexts to motivate the study of abstract mathematical
contents. Also, it should give sufficient feedback and be able to adapt
to the needs of various learners. The purpose of the paper is to discuss
basic pedagogical principles that may serve as starting points and guidelines
in the evaluation of hypermedia-based learning environments. Two existing
hypermedia learning environments will be introduced and evaluated on the
basis of the pedagogical principles presented.
Key Words: Hypermedia-based learning environment, evaluation,
constructivism, collaboration, intention, context, transfer, reflection.
1 Introduction
Rapid development of information technology, especially in hardware,
software, and telecommunication, has increased the potential of technology
in education. To take full advantage of the possibilities that modern information
technology provides, learning theories must be developed and incorporated
into the design of computer based learning. Modern learning theories emphasise
the importance of context and collaboration when integrating technologies
in learning. Constructivism has risen to be an essential theory in the
research of technology-based learning environments. This approach has been
applied in the mathematical sciences, too. Constructivism learning is seen
as a building process in which learners have an active role and learning
is based on their cognitive functioning. The learners obtain new knowledge
by constructing it on the basis of their earlier knowledge, upon their
active
functioning in continuous interaction with the surrounding reality and
other learners. The purpose of this paper is to introduce important pedagogical
principles that can be used as guidelines in the evaluation of learning
environments. The proposed qualities of learning are based on the list
proposed by Jonassen [1995]. The rules of the use
of technology in the evaluation on learning environments are based on Jonassen's
list of qualities of meaningful learning.
A "moderate" constructivistic approach [Reusser
1991a] emphasises teacher's and content provider's essential role in
cognitive development and knowledge construction using carefully designed
and presented learning materials, and technologies. Tutoring and teacher's
functions support learning as well as appropriately designed didactic materials
and they give students possibilities to develop their skills and become
more independent and self-regulated learners.
The above principles will be applied to two existing hypermedia learning
environments; Solver and Mathematical Microworld for WWW (MMWWW).
Solver is a technology based learning environment for mathematical
word problem-solving, intended to be used in schools as an additional material.
MMWWW contains university level mathematics courses in the form
of hypermedia. These courses can be studied on the Internet. The environments
will be presented and analysed in respect to the list of qualities of meaningful
learning. [Ruokamo-Saari, H., Pohjolainen, S. 1997.]
2 Seven Qualities of Learning
We would like to emphasise the seven qualities of learning, given below,
suitable in learning from school to university level. This list of qualities
of learning is based on Jonassen. The authors have joined the conversational
and collaborative qualities in Jonassen's list into one and added the quality
of transfer into the list. From our point of view the seven qualities of
learning are as follows:
- Active - Learners' role in learning process is active; they
are engaged in mindful processing of information and they are responsible
for the result.
- Constructive - Learners construct new knowledge on the basis
of their previous knowledge.
- Collaborative - Learners work together in building new knowledge
in co-operation with each other and exploiting each other's skills.
- Intentional - Learners try actively and willingly to achieve
a cognitive objective.
- Contextual - Learning tasks are situated in a meaningful real
world tasks or they are introduced through case-based or problem-based
real life examples.
- Transfer - Learners are able to transfer learning from the situations
and contexts, where learning has taken place and use their
knowledge in other situations.
- Reflective - Learners articulate what they have learned and
reflect on the processes and decisions entailed by the process.
All these qualities are interactive, interrelated, and interdependent
with each other. In what follows the authors will use these qualities of
learning when evaluating the two mathematical learning environments.
3 The Use of Technology in Learning
Jonassen [1995] presents some assumptions about
technology in learning. In his point of view educational technology can
be seen as follows:
- Technology is more than hardware. Cognitive learning strategies,
critical thinking skills and replicable, applicable techniques can be engaged
with the learner via using technology.
- Learning technology can engage learners in knowledge construction
and meaning-making.
- Knowledge construction is not supported by technologies used
as conveyors of instruction that prescribe and control all learners interaction.
- Technologies will support knowledge construction better when
they are need- or task-driven, when interactions are learner-initiated
and learner-controlled, and when interactions with the technologies are
both conceptually and intellectually engaging.
- Technologies as tool kits enable learners to build more meaningful
personal interpretations and representations of the world. They must support
the requisite intellectual functionality of the learning requirements of
the course of the study.
- Learners and technologies should be intellectual partners. Cognitive
responsibilities for performing should be distributed by that part of the
partnership that performs it best.
The useful principles listed above should be used in pedagogic design
and evaluation. According to Reusser [1995] the design
of a computer-based instructional system should be based on content specific
research of learning and comprehension and pedagogical model of the learner
and the learning process. In designing computer-based teaching and learning
environments, real didactic tasks should be considered. One should think
thoroughly what to teach and how to teach. The essence of pedagogical design
is in the didactic analysis of concepts, structures, representations, learning
methods, skills, and strategies and learning models in relation to task
or domain specific factors.
These guidelines about technology in learning should also be used in
the evaluation
of hypermedia-based learning environments. In the next section two existing
hypermedia based learning environments will be evaluated in respect to
the principles given above.
4 Evaluation of Two Hypermedia-based Learning Environments
4.1 Case Solver - a Learning Environment for Solving Mathematical
Word-Problems
Solver is a technology-based learning environment that also includes
different presentation forms of hypermedia (e.g. hypertext, graphics, animation,
sound, video) and network properties, social interaction, physical learning
activities and mental thinking processes in learning situation [See Ruokamo-Saari
1996a; b.].
Solver has been used to study the connection between the level
of students' mathematical giftedness and development of their problem-solving
skills when working in a technology-based learning environment [Ruokamo-Saari
1997a; b]. Solver was designed on the
basis of an existing computer-based program developed for word problem-solving
by Reusser et.al. HERON [see Reusser 1988,
1991a, 1991b; Staub
et.al. 1994; Reusser 1995]. In the Solver
environment students solve word problems by constructing solution trees
with cognitive tools. This process ends up with final result that solves
the problem posed in the text.
In Solver the properties of on- and off-line hypermedia are connected
together. The on-line part was designed to be used via the WWW and the
off-line, local part was programmed with Multimedia ToolBook 3.0. Figure
1 presents the design of Solver application (in Finnish): the tools,
solution tree, and equation in off-line ToolBook application are
on the right and the tools and problem text of an on-line HTML document
are on the left.

Figure 1: The user interface of Solver with on-line and off-line
tools
Problem tasks, hints, the model solutions, and a bulletin board are
programmed using HTML, so that these can easily be distributed via network,
and they can be updated later on. In creating the problem situations a
contextual approach was adapted: the topics chosen for the word problems
was based on student inquiry: the students were asked about real life problems
they would like to solve. Video material was produced to introduce the
problem situations for students.
In the problem text there are hot words. By activating them students
can get definitions, rules, formulas, and other information about the subject.
If a problem is too complex to solve, the user may select the hint tool
to obtain tips for constructing the solution. Students may ask hints from
each other in problematic situations when constructing the solutions. Using
the bulletin board, students are able discuss with other students or with
their teacher methods for solving the problems. On the basis of these conversations
they can further develop their own constructions.
In the program the model solution for a given mathematical problem is
presented step by step, and the students are assumed to discover the solution
procedure. Gifted students can probably find shorter or alternative ways
to solve the problems. The students' solutions can also be saved and analysed
later on.
Some Principles of Tutoring
Solver does not tutor students in the problem-solving process,
unless asked for help or hints. This property was thought to be suitable
for especially gifted problem-solvers who do not necessarily need any tutoring
but are able to conduct autonomous and
original problem-solving. Tutoring was designed with those students'
needs in mind who had difficulties in problem-solving. It is also important
that students have a chance to notice by themselves possible mistakes they
make during problem solving. When a user asks for a hint during the solution-process,
Solver tries to find context sensitive hints related to the user's
situation in his/her solution. If the user's way of constructing the solution
is very original and Solver can not help him/her, it asks the student
to try to find support from other students via bulletin board or to go
on and check the final result at the end with the checking tool.
The user can start modeling in any situation and move on to an open
solution space. In principle, he/she is able to construct the whole solution
without tutoring until the final stage, where Solver asks the student
to evaluate the final equation. If the user makes mistakes in constructing
the solution, the checking tool informs him or her about wrong results.
After checking the results, the user can see a representation of the model
solution and can compare it with his/her own solution. Even if the solutions
are not similar, they can be correct. All the students solutions are saved
to files, so that the problem-solving processes can be examined and compared
later on. The new solutions proposed by the student can be used as examples
of alternative ways to construct solutions.
4.2 Case: Mathematical Microworld on WWW
The pilot hypermedia material consists of two university courses: Introduction
to University Level Mathematics and a course on Matrix Algebra. The purpose
of the first course is to review school mathematics and to provide help
and support for mathematical problems that students will be facing at the
university level. The second is a postgraduate course in mathematics at
Tampere University of Technology (TUT). The courseware has been designed
to be used on the WWW [Antchev et.al. 1996] (http://matwww.ee.tut.fi).
The structure of both of the courses consists of text, a mathematical dictionary
or database of definitions of mathematical concepts, exercises, examples,
and computer aided interactive exercises. The most important mathematical
ideas algorithms and problems are clarified with animations and video clips.
The mathematical concepts in the lecture notes are linked to the corresponding
definitions in the mathematical dictionary or the definition database to
provide on-line help for understanding them. Exercises, with hints and
examples, are given as a part of the lecture notes. The symbolic algebra
package, Mathematica, is used for interactive exercises; it generates
various numerical and symbolic exercises, and checks the answers given
by students. Interactive exercises provide feedback for the students. In
a typical interactive exercise the computer will pose a problem and ask
the student to fill in an on-line form. In some cases the user may be asked
to answer the problem. The answer will be assessed and a message will be
returned describing whether the answer is correct or what went wrong. A
part of the problem's data is randomised so that the students can work
out several problems of the same type, successively. They may explicitly
ask for "new values" to be generated by pressing a
designated button, or students may simply arrive several times at the
same node. Additionally, the numerical simulation program Matlab
is used as a part of the numerical exercises.
The basic structure of the hypermedia courses is based on the experiences
that the authors have got from constructing a stand-alone hypermedia learning
environment for Macintosh [Pohjolainen et.al. 1994, 1997].
Positive classroom experiences encouraged us to extend the basic design
ideas for the WWW version [Multisilta et.al. 1994,
Pohjolainen et.al. 1996]. Communication between distant
learners and teachers is supported by bulletin boards, e-mail, and video
conferencing software.
Studying Matrix Algebra on the WWW
A general view of the learning interface in the course of Matrix Algebra
is given in Figure 2. The instructional material consists of lecture notes
divided into chapters and subchapters, a concept definition database, exercises,
interactive exercises, animations, and videos. In the figure the student
is reading the subchapter on the Jordan Canonical Form. On the left hand
side there is a page from the lecture notes (in Finnish). The links starting
from the mathematical concepts to their definition files can be seen as
the anchor words and they are underlined or of a different colour. The
student has also opened a video tutorial that shows how to find the Jordan
Canonical Form for a given matrix. At each stage of the solution the video
tutorial presents the theoretical results that are needed for the next
stage. The hand-writing in the video window is used to tell the student:
this is what you should do. Since video clips contain sound, they give
a possibility to pass oral information to students. This is useful to teach
the pronunciation of Greek letters, names of mathematicians, (foreign)
names of methods, and so on. Looking and listening to the video may help
the student to solve a related interactive exercise, generated by a symbolic
algebra program Mathematica (lower right hand corner) [Antchev
et.al. 1995]. From this point of view it is useful that the video can
be stopped and be viewed frame by frame. Once the student has found the
solution, he or she may write it down in a box provided. After that, the
computer checks the solution and informs the student about the result.
The correct solution can be seen by pressing the "Show the right answer"
button. If the student wants to find the Jordan Canonical Form for another
matrix, he/she may ask for a new matrix by pressing the "New Values"
button. Care has been taken to keep the problems sufficiently simple. All
the matrix algebra interactive exercises can be solved with integer matrices,
with small integer elements. Currently there are 15 interactive exercises
in the course of matrix algebra.

Figure 2: Learning interface of the WWW-microworld
In addition to Figure 2, the microworld contains exercises, mostly theoretical,
with two hint levels. The first hint level explains the problem in more
detail and the second hint level informs about the right path for the proof
of the solution. All this textual material is given as hypertext, and links
to the definition files are available.
As a part of the hypertext lecture notes, a student can find previous
examination problems. These can also be read as hypertext with links to
the definition files, and they can be used also as test questions for self-study.
At the end of each page there are two buttons which give possibilities
for student-teacher interaction. The student can open the bulletin board
and communicate with other students and a teacher of the course by pressing
the leftmost button at the lower left corner of the lecture notes in Figure
2. The button on the right opens a form for e-mail between the student
and the teacher.
Students may also contact the teacher in a more personal way. At the
end of each page of the hypernotes they may find buttons to send e-mail
to the teacher. This feature will be used to give the students personal
assistance, to receive their solutions to given problems, and to give them
personal feedback. The possibility of attaching documents with e-mail is
especially useful, since it allows the sender to point out details on the
WWW material.
In the next section Solver and MMWWW will be evaluated
and compared on the basis of the seven qualities of an appropriate learning
environment presented earlier.
5 Evaluation of Solver and MMWWW
A direct comparison of the two hypermedia learning environments is rather
problematic because of the differences in their design principles, user
groups, and goals. Solver is a technology based learning environment
for mathematical word problem-solving, intended to be used in schools as
additional materials. MMWWW contains university level mathematics
courses in the form of hypermedia. The courses can be studied over the
Internet. In spite of the differences in the nature of the environments,
the authors still feel the comparison to be useful, but rather in the sense
that environments are evaluated in regard of the seven qualities rather
that compared against each other.
In Table 1, Solver and MMWWW are compared in regard to
the seven qualities of appropriate learning environment presented above.
Qualities |
Solver |
MMWWW |
1. Active |
- students have made proposals for what kind of real life problems they
would like to solve and would be interesting for them
- students have an active role in whole problem-solving process and in
the construction of the solution
- students are responsible for constructing the solution via solution
trees and for the whole problem-solving process including the final result.
|
Students have an active role in navigating and in selecting the order
of the material they are studying (e.g. a student may study the theory
directly from problems)
the student may study parts of the material using various forms of
media: text, video tutorials, tool programs, or as a combination of them
students are asked to solve numerical exercises that the computer checks
|
>2. Constructive |
- students construct solutions via solution trees with cognitive tools
- students construct the solutions on the basis of their previous knowledge
in interaction with other students
|
students construct new knowledge by studying the theory and by solving
carefully selected problems
Matlab scripts are used as cognitive tools in the construction
of knowledge
|
3. Collaborative |
- all the students collaborate with their student partner and other students
via bulletin board
- students may also collaborate with the teacher. The teacher's role
is to guide and support students' problem-solving processes
|
students collaborate with other students using bulletin board
students collaborate with teacher using email
|
4. Intentional |
- problem situations were designed taking into account students' age
and interests of different genders
- students may solve problems that are anchored in real world problem
situations
- students may see that skills to solve these problems are useful in
their every-day life
|
the engineering students may solve problems that are related with their
field of interest
students in mathematics may see how mathematics can be applied
|
5. Contextual |
- contexts and the problem-situations - that might be interesting for
students - were chosen on the basis of the student inquiry
- problem situations were anchored to real life contexts: e.g. home party
- each of the six problem situations consists of six word problems connected
to each other
- titles for the situation elements can be used as hints in constructing
the solution tree
- hint tool provides context sensitive hints by comparing the model solution
with the student s solution
- hints are related to the situation where students are in their problem-solving
process
|
mathematical applications in engineering and other fields of science
are presented
video clips of the use of mathematics in everyday life are given to
present real-life situations
|
6. Transfer |
- problem-solving process can easily be transferred from one problem
situation and problem to another situation and problems and to real world
|
randomised numerical data in interactive exercise makes it easier for
the student to learn the essence of the method or algorithm under study
and separate it from its numerical presentation
Problems related in mathematical applications in engineering help the
students to apply their skills in practice
|
7. Reflective |
- students articulate while problem-solving with other students either
directly with student partner or by using the bulletin board with other
student pairs
- students may articulate with teacher also
- students have to understand their processes to be able to articulate
with others, they can utilise these articulations in guiding their processes
further
- students may evaluate and compare their final results from the solution
spaces and model solutions, or they might use saved files, log-files, or
print outs
- after the lessons two student pairs participated in STRI-interviews
where they evaluated their problem-solving processes on the basis of taped
videos (including their faces and computer screens) during their problem-solving
|
theoretical problems are presented with two hint levels. The hint levels
needed in the solution reflect the learner's skills
Interactive exercises form a way for the learner to gain feedback about
how well (s)he is able to solve numerical problems
|
Table 1: The comparison of Solver and MMWWW in respect to
the seven qualities
6 Conclusions
In this paper seven important qualities of learning have been introduced
and used in the evaluation of hypermedia learning environments for the
mathematical sciences. Two learning environments; Solver and MMWWW,
have been evaluated on the basis of the qualities presented. Solver
was designed for secondary school level for mathematical word problem-solving
and MMWWW contains university level courseware on the web. In regard
to the seven qualities presented, the learning environments can be improved
in many ways.
To strengthen the qualities of activity, constructivity and collaborativity
in the Solver environment it might be useful to include a tool to
enable students to show their solution trees to other students. On the
basis of these solution trees, which are visible for everybody, all the
students could elaborate jointly their problem-solving processes. It should
also be useful if students were able to point out situations from their
solution trees, and to reconstruct them in collaboration with other
students. Students should also be able to save their correct
solution trees as model solutions, if these differ from the solutions given
by Solver. Multiple model solutions can also be used to improve
the functioning of the hint tool. Currently the hint tool can give hints
only when the students' solution tree resembles the given model solution.
This would also improve the context sensitivity of the hint tool.
In the MMWWW learning environment the students activity should
be strengthened in construction of knowledge. Students should have special
tools to support knowledge construction, e.g. the use of mathematical programs
such as Maple and Matlab should be integrated to be an essential
part of the learning tasks. This would also strengthen the students' activity,
intention and reflection, as they could elaborate and solve "real
world" problems using sophisticated theoretical methods.
Secondly, collaboration is not supported strongly enough in MMWWW.
The students need more specific exercises and tasks to be solved in collaboration.
Currently the students may send e-mail and discuss with other students
and teachers via bulletin board, but the use of communication tools is
not integrated with the learning tasks. Students' reflectivity should be
improved, too. They should be able share and discuss their learning processes
with other students, get feedback and guide their learning processes further
on. In addition to interactive exercises and hinted exercises, students
need more tools to express their real understanding and to evaluate their
learning processes and more open tasks should be included in the learning
environment to improve the property of reflection.
From the author's point of view the evaluation of learning environments
has been
useful, and the results will be used to improve the existing learning
environments and they will guide our research and development work further
in the field on web-based open learning environments.
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