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The assessment of
students' mathematical knowledge should yield information about
their--
- ability to apply
their knowledge to solve problems within mathematics and in other
disciplines;
- ability to use
mathematical language to communicate ideas;
- ability to reason
and analyze;
- knowledge and understanding
of concepts and procedures;
- disposition toward
mathematics;
- understanding of
the nature of mathematics;
- integration of
these aspects of mathematical knowledge.
Focus
In mathematics, as in any
field, knowledge consists of information plus know-how. Know-how
in mathematics that leads to mathematical power requires the ability
to use information to reason and think creatively and to formulate,
solve, and reflect critically on problems. The assessment of students'
mathematical power goes beyond measuring how much information they
possess to include the extent of their ability and willingness to
use, apply, and communicate that information. The assessment should
examine the extent to which students have integrated and made sense
of information, whether they can apply it to situations that require
reasoning and creative thinking, and whether they can use mathematics
to communicate their ideas. Additionally, assessment should examine
students' disposition toward mathematics, in particular their confidence
in doing mathematics and the extent to which they value mathematics.
An assessment of students'
mathematical power is broad in scope and should include all
the aspects identified in this standard and determine the extent
to which they are integrated. The assessment of mathematical power
should not be construed as the assessment of separate or isolated
competencies. Although one aspect of mathematical knowledge might
be emphasized more than another in a particular assessment, it should
remain clear that mathematical power concerns all aspects of mathematical
knowledge and their integration.
Discussion
To have assessment practices
in mathematics that reflect these standards, all important aspects
of mathematical knowledge must be assessed. Student-assessment standards
5-10 address each of these aspects and how they are interrelated
and give guidelines for assessing them. This discussion focuses
on determining the extent to which these aspects are integrated.
Problem situations from
different areas of study offer a rich context in which to assess
students' mathematical power. Problems derived from such situations
typically require students to apply a variety of mathematical concepts
and procedures and engage in some form of mathematical reasoning.
Understanding these concepts and their interrelationships is essential
to interpreting a situation and deriving an appropriate plan of
action. Knowing what procedures are appropriate or necessary and
how to execute them is essential to carrying out the plan successfully.
Furthermore, these problems require students to use various forms
of reasoning to arrive at a solution. Consider, for example, the
following task derived from a social studies lesson on the commerce
between North America and Hong Kong:
Pretend you are a pilot
for a major airline-transport company. You have been assigned for
the first time to a trans-Pacific flight from New York to Hong Kong.
You are curious about the shortest route between the two cities,
but all you have is a regular globe and a piece of string. You know
that the distance around the Earth along the equator is 25 000 miles.
With only these two items, how can you figure the shortest distance?
What is this distance?
The task requires students
to interpret the shortest distance between two points on a sphere,
find a way of measuring that distance, and use proportional reasoning
inventively and creatively. The task is suitable for junior high
school students. Students can work individually or in small groups
while the teacher observes their interactions. These observations
can yield information about the students' ability to apply their
knowledge in solving the problem. This task illustrates how mathematics
can be integrated into other areas of the school curriculum.
The assessment of students'
mathematical power is appropriate at all grade levels and should
not be delayed on the grounds that students must know a great deal
of mathematics before they can integrate this knowledge. Group tasks
are particularly useful in the lower grades for assessing the integration
of students' mathematical knowledge. At the K-4 level, a group task
like the following can be devised:
| Materials Required |
Task |
- Large box of raisins
- Containers of different sizes
- Balance
- Calculator
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- Estimate the number of raisins in the box.
- Use any of the materials to make a better estimate.
- Check your estimate by different methods.
- Record your results and give an oral account of your
work.
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The assessment of students'
performance on this task focuses on their choice of an overall solution
strategy. A successful approach entails counting the number of raisins
in a small unit and relating the smaller unit to the whole (the
large box) in some way. Students can use a balance to halve successively
the number of raisins until a manageable number is obtained and
then multiply to obtain the total in the large box. Or they can
count the number of raisins in a small container and find the number
of small containers necessary to fill the large box. Or they can
measure the height of a small proportion of the raisins in the large
box and the height of the full box and relate the two heights. Whatever
their strategy, students engage in counting, computing, measuring,
and communicating to perform the tasks.
Reporting on the students'
strategy can be done using a rating scale. Evidence of students'
application of their strategy is obtained from the recorded results
and oral accounts of what they did. Levels of mathematical argument
can be similarly evaluated. An assessment of the mathematical concepts
and procedures used can focus on the accuracy of counting and calculation;
the correct choice of operation; the understanding and use of balance;
and such calculator skills as accurate keying, recognition of the
order of operations, and correct interpretation of the display.
Finally, the assessment of communication skills can focus on the
students' recorded and oral accounts of their work.
Problems and group tasks
are not the only means of assessing the integration of students'
mathematical knowledge. Written tasks can be used effectively. A
written task can consist of multiple subtasks, encompassing various
aspects of mathematical knowledge and their integration. Figures
4.1, 4.2, and 4.3
contain an example (Swan 1987,
pp. 28-30) that illustrates this approach:
Fig. 4.1.
Map showing distance from school to home
Fig. 4.2.
Length and time of journey
Fig. 4.3.
Speed by distance for Peter's journey
The graph in figure
4.2 describes each pupil's journey to school last Monday.
- Label each point on
the graph with the name of the person it represents.
- How did Paul and Graham
travel to school on Monday?
- Describe how you arrived
at your answer in part b.
- Peter's father is
able to drive at 30 mph on the straight sections of the road but
has to slow down for the corners. Sketch a graph on the axes in
figure 4.3 to show how the car's speed
varies along the route.
The assessment of students'
performance on this task focuses on their ability to apply several
mathematical concepts, skills, and processes simultaneously. The
task entails reading, interpreting, and selecting information from
the map and combining it with information in the problem to estimate
the children's relative travel times and establish the correspondences
between points on the graph and the children. The selection and
use of information necessary to label the points on the graph entails
an understanding of the relationship among distance, time, and speed.
Students must apply their knowledge of coordinate graphs and the
variables represented to establish a correspondence between points
and children. Additionally, they must infer from the graph the mode
of travel used by two of the five children. The students' description
of their reasoning in labeling those points offers evidence of their
ability to communicate mathematical ideas. Finally, the task calls
for the graphical representation of a car's speeds along the route
depicted in the map, which requires the simultaneous consideration
of the route, the additional information in part d, and the
variables represented in the graph.
Students' responses to
this task can be evaluated by rating their ability to read and interpret
information in the map, combine this information with that in the
problem statement, and translate and summarize it in a graph. Marks
can be given for correctly identifying each point in figure
4.2. The students' description of their reasoning in locating
those points can be assigned marks if Paul and Graham are identified
as cycling or running or if the explanation matches the graph drawn
in figure 4.2. The response to figure
4.3 can be assigned marks on the basis of the inclusion of the
main features of the graph--correctly locating endpoints, indicating
two minima in the correct position, showing the speed as 30 mph
for at least 1 mile in the middle section of the graph, and correctly
recording all other features of the graph. The score for the tasks
would be the sum of the marks given.
Written tasks such as these
can be useful in determining the extent to which students' knowledge
of mathematics has been integrated. However, such assessment cannot
be based solely on students' performance on a single task, regardless
of how valid or appropriate the task might be. To assess the integration
of mathematical knowledge, information must be obtained from several
tasks performed over time in a variety of contexts.
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