Russian Mathematics Education: Programs and Practices
a sum. Dividing a sum by a number. Oral and written calculations
with natural numbers. Using the properties of arithmetical opera-
tions in calculations. Finding an unknown component of arithmeti-
cal operations. Strategies for checking calculations. Solving word
problems (with one or multiple operations) by arithmetical means
(using a variety of models: schematic drawings and graphs, tables,
and shorthand notations with keywords). Relations of proportional
magnitudes (velocity, time, distance traveled; price, quantity, cost,
etc.).
As for other subjects, let us note that we do not see the advantages
of a detailed study of decimal fractions — i.e. construction, rounding,
comparison, performing arithmetical operations, and deriving fraction
from number and number from fraction — at the fourth-grade level
(Alexandrova, 2009). In moving this material from the fifth- and sixth-
grade curriculum into elementary school, the textbook runs counter
to the principle of succession and shifts attention from other important
topics (for example, at the second- and third-grade levels, this textbook
has far too few exercises with geometrical figures).
We are also skeptical about the accessibility for students of propor-
tions characterizing work, movement, and buying–selling (Davydov
et al., 2009), in order to understand which students need to master such
concepts as “process,” “event,” “variable characteristics,” “additional
conditions,” “uniform process,” “variable process,” and “speed of a
uniform process.” In the corresponding textbooks for the fourth grade,
one reads: “The speed of the uniform process K indicates the rate of
increase of Y with respect to X. X
1
= X
2
, Y
1
> Y
2
, K
1
> K
2
.” And
further on: “The speed of a uniform process is a constant. It indicates
how many units of Y correspond to a single unit of X” (Davydov et al.,
2009, Book 1, p. 109).
It is interesting to note the use of the calculator (Chekin, 2009;
Istomina, 2009; Moro et al., 2009) not as a substitute for manual
calculation, but as a way of verifying results. Here are a few sample
exercises:
• Find the value of the expressions 37 + 24 − 24, 52 + 37 − 37, and
83
− 18 + 18.
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The History and the Present State
69
In what ways are these expressions similar? What conclusions can
you draw? Verify your results with the help of a calculator, using
different numbers. (Istomina, 2009, 2nd grade)
• Using a calculator, add 1, 2, 3, and 4 to the number 372. Which
digit changes in the number 372? What other numbers could
you add to 372 without changing any of the other digits in the
number? (Istomina, 2009; 2nd grade)
• Using a calculator, find out whether the greatest three-digit
number is a multiple of the greatest six-digit number. (Chekin,
2009; 3rd grade)
• The value of what expression would you be calculating if you
pressed the following sequence of buttons on your calculator?
2
3
8
9
7
7
−
2
3
8
9
0
5
÷
9
(Chekin, 2009, 3rd grade)
The introduction to algorithms in several of the textbooks includes:
analyzing existing algorithms; constructing new algorithms (including
“everyday life” algorithms — crossing the street, lighting a fire, etc.);
types of algorithm notation — verbal and flowchart; and performing
calculations using a flowchart. This addresses the requirements set out
in the new standard.
A number of “complexes” pay special attention to estimating value,
evaluating results, and verifying results. For example, Ivashova et al.
(2009) include the following assignment:
Calculate and verify using a different calculation technique, such as:
100
÷ 4 = (80 + 20) ÷ 4 =
60
÷ 4
90
÷ 5
100
÷ 4 = (120 − 40) ÷ 4 =
14
· 5
38
· 2
Bashamkov and Nefedova (2009) have the following:
Choose the answer out of three given values without performing the
calculation to the end. Then evaluate the value and compare it with
your choice.
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