Russian Mathematics Education: Programs and Practices
Find the value and compare it with your choice.
(a) 173
+ 264 + 435, (b) 236 + 312 + 422, (c) 329 + 119 + 449
m
872
m
972
m
899
m
772
m
970
m
997
m
874
m
890
m
897
Moro et al. (2009, 4th grade, p. 85) have the following:
Pick out the wrong answers without doing the calculation. Solve and
check your answer through multiplication.
7380
÷ 9 = 82, 3010 ÷ 5 = 62, 56014 ÷ 7 = 8002.
Some of the textbooks include subjects not covered in the standard:
“Common fractions, addition and subtraction of fractions with the
same denominator, multiplication and division of fractions,” “Positive
and negative integers,” and “Percent.”
As far as calculation techniques are concerned, let us note the
following: the majority of the textbooks first teach oral calculations
and then written calculations. Davydov et al. (2009) first introduce
the digit-position principle of written calculation and only later ask
students to compose and memorize a table of addition (and later
multiplication) and learn the techniques of oral calculation. It seems
advisable to encourage students to calculate orally whenever possible.
Rudnitskaya and Yudacheva (2009) give primacy of place to written
calculation, which seems to us a doubtful approach, since in everyday
life one is often called upon to calculate “in one’s head.”
7.2.2
Arithmetical problems
Students learn to analyze the problem, establish connections between
magnitudes, determine the number and type of operations necessary
for solving the problem, choose and explain their choice of operations;
to solve the problem using arithmetical methods (in one or two, or
even three or four steps), including proportional magnitudes; and to
find multiple solutions to the same problem.
Some of the curriculum “complexes” — see e.g. Moro et al.
(2009) — use basic problems to demonstrate the concrete meaning of
operations and to teach concepts such as “by certain amounts/certain
times greater/less than,” properties of operations, and so on. Problems
March 9, 2011
15:1
9in x 6in
Russian Mathematics Education: Programs and Practices
b1073-ch02
The History and the Present State
71
are introduced gradually, and every time a problem is first given with
sets, then with magnitudes, and finally with abstract numbers. In
other “complexes” — see e.g. Istomina (2009) — students first learn
the skills described above, then apply them to specific problems. In
Peterson (2009), Davydov et al. (2009), and Alexandrova (2009),
all basic problems solved by addition or subtraction are illustrated
with schematic graphs and explained as a relation of whole and parts.
All textbooks (beginning with the first and second grades) include
compound problems, and — starting in the third grade — problems
with proportional magnitudes. Children are frequently asked to look
for alternative solutions to the same problem. For example, Demidova
et al. (2009, 4th grade, pt. 1, p. 88) include the following problem:
How many different ways can you find of answering these questions?
To travel 80 km along a river in a motorboat, one needs 160 L of
gasoline. How many liters of gasoline does one need to travel 40 km
more? How much farther can you travel if you have 20 L of gasoline
more?
Many textbooks contain problems with missing or extraneous
information, with data given using letters rather than numbers, and
with exercises involving problem change and problem composition.
7.2.3
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