JOURNAL
SUMMARY
Pramudiani, P.,
Zulkardi, Hartono, Y. & Ameron, B.V. (2011). A concrete situation for
learning decimals. Indonesian
Mathematical Society Journal on Mathematics Education, Vol. 2, No. 2, July,
(2011), 215-230.
It was found
that decimals is an essential part of mathematics whose concepts need to be
learned meaningfully in order to prevent students from misconception. The fact,
however, showed that Indonesian textbooks could not provide such condition and neither
do the learning and teaching activities which finally led the students to the
lack of understanding and misconception toward the concept. RME underlying the
design of context (in this case precise measurement) and activities seemed to
be an appropriate solution regarding this problem. Therefore, the study was
conducted, that is, to study how measurement activities promote students’
notion of decimals.
The research was
conducted in three main steps, namely, preliminary design (to produce a
conjectured local instruction theory containing learning goals, planned
activities, and learning process), teaching experiment (involving 26 students from
class 5A SDN 21 Palembang in 6 lesson hours, prior to this, 73 students were
involved in the pre-assessment and pilot experiment was given to 7 of them each
from high, average, and low level students), and retrospective analysis
(analyzing data collected and comparing the hypothetical learning trajectory
with the students’ actual learning).
During the
teaching experiment, the students did activities given in 4 level structures.
The first phase called situation level provides students with context, where,
the students are asked to weigh duku, body, rise and to measure the volume of
beverages. Next, referential level, the students were directed to display their
measurement results using stripes on the number line. Using number line to
determine the magnitude of decimals was done in general level and the last, in
formal level, the students were guided to compare decimals without relying on
number line.
The study found
that: 1) measurement activities helped the students to realize the existence of
numbers between two consecutive whole numbers, 2) scale visualization involving
sequence of numbers led the students think of using number line as a model for
placing magnitude of decimals, and 3) number line plays a big role in bridging
the experience-based activities into a more formal mathematics. Finally, based
on post assessment result, most students, 85%, earned a good understanding of
decimals.
#for a complete journal, you may visit: http://jims-b.org/?p=362#
