Özet:

In this study, it was aimed to investigate the eight grade students’ performance on drawing graphs of real world situations, to what extent they can interpret unit rate and rate of change concepts with its different representations (geometric and algebraic ratio, functional property), and how they relate different slope representations with each other. In addition, it was examined to what extent they can relate the given situations with the slope concept. Participants consisted of 158 eight-grade students who were selected from two public schools via convenience sampling. First, four-open ended and its sub-problems were used as data collection instrument. One of those problems included static situation and three of them included dynamic real world situations. While formulating sub-questions, different slope representations including physical property, functional property, algebraic ratio, geometric ratio and linear constant were considered. Next, task-based interviews were held with four students selected based on their responses to the four problems. The findings of this study showed that most of the students could calculate the rate of change or unit rate correctly however, they sketched graph by coordinating pairs and they used graphics as figurative while explaining representations of slope. It was also seen that students who had an understanding of geometric ratio in the static situation met a challenge of relating representation of geometric ratio with functional property and linear constant representation in the interviews. In addition, it was found that, students associated the slope concept more with the static context than dynamic contexts. Therefore, to make students to establish relations between different representations of slope, it is important to use the graphical displays of both dynamics and static situations as operative.

Anahtar Kelimeler: