Russian Mathematics Education: Programs and Practices
dealing with elementary trigonometric equations and inequalities. The
test contains 10 problems in all.
1. Solve the equation cos 0
.5x = −1.
(a)
x = 3π + 4πn, n ∈ Z;
(c)
x = π + 2πn, n ∈ Z;
(b)
x = 2π + 4πn, n ∈ Z;
(d)
x = 0, 5π + 0, 5πn, n ∈ Z.
10. Solve the inequality sin
x > cos x. In your answer, indicate the
sum of the natural numbers that are less than 10 and satisfy the
given inequality.
(a) 17;
(b) 30;
(c) 6;
(d) 23.
The author established the following criteria for grading: a five for
9–10 correct answers; a four for 7–8; a three for 5–6; and a two for 4
and fewer. He recommended giving students one-and-a-half hours —
two combined classes — to complete the test. However, the advisability
of devoting two class periods to this work is open to doubt, because a
good student will complete the given assignments in approximately 30
minutes while a weak student might never complete them at all, if only
because problems that involve trigonometric inequalities go beyond
the bounds of the standard public school curriculum.
Let us turn to examples of more difficult multiple-choice tests in
geometry (plane geometry) for students in grades 7–9 in classes with
an advanced course of study in mathematics (Zvavich and Potoskuev,
2006a, 2006b, 2006c). The book in which these tests appeared
contained subject tests, survey tests, and summary tests. Each of them
consisted of 16–17 problems in plane geometry and each was meant
to be completed in 40–45 minutes. The authors recommended giving
two fives for 16 correct answers, one five for 14–15 answers, a four for
12–13 answers, and a three for 9–11 answers. They also considered an
alternative grading method, in which students would receive two points
for every correct answer, have one point deducted from their total for
every wrong answer, and be given no points if they left the answer
to a question blank. With this approach, the scores would range from
−16 to 32. Such a grading method is likely to eliminate meaningless
guesswork, but in our view it is too complicated for both students and
teachers. Below are three problems from a subject test devoted to the
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Russian Mathematics Education: Programs and Practices
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Assessment in Mathematics in Russian Schools
335
Pythagorean theorem (note that problem 15 is marked with an asterisk,
indicating a higher level of difficulty).
1. The points
K, M, T , and P are located on sides AB, BC, CD,
and AD of the square ABCD, respectively, in such a way that
AK
= 3, KB = 5, and BM = CT = DP = 3. Find the area of
the quadrilateral KMTP.
(1) 34;
(2) 36;
(3) 49;
(4) 53;
(5) 16.
14. Find the distance from the center of a circle with radius 4 to any
chord of the circle of length 4.
(1) 3
√
2
;
(2) 2
√
3
;
(3) 2;
(4) 3;
(5) 1.
15
∗
. The diagonal of a right trapezoid divides this trapezoid into two
right isosceles triangles. Find the length of the center line of this
trapezoid if the length of its diagonal is equal to 2
√
2
(Fig. 1).
(1) 1;
(2) 2;
(3) 3;
(4) 4;
(5) 5.
As can be seen, these problems are sufficiently traditional for an
in-depth Russian school course in plane geometry. Thanks to the
multiple-choice format, many of the usual requirements are eliminated
(explanation and substantiation, mathematically exact notation, the
construction of an exact diagram, etc.). Students who have completed
a large number of these demanding problems within the allotted
time should hardly be suspected of having assimilated this material
in a merely formal and superficial manner, and they should hardly be
required to demonstrate their understanding by indicating all of the
theorems on which they relied in solving these problems. At the same
time, of course, it is much easier to correct and grade such tests than
the more traditional variety.
Fig. 1.
March 9, 2011
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Russian Mathematics Education: Programs and Practices
b1073-ch08
336
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