Twenty-three contextualized problem-solving tasks were used in U.S. classrooms and 26 contextualized problemsolving
tasks in Chinese classrooms. Two of the U.S. contextualized problem-solving tasks were problem-posing
tasks: (1) Create a story problem that requires you to compare 9/15 and 20/24; (2) Design a situation in which
you would want to change a mixed number to an improper fraction. Both of these tasks came from Ms. T’s second
lesson. U.S. teachers used verbal representations for six of the 23? contextualized problem-solving tasks (25%).
On 15 of the contextualized problem-solving tasks, U.S. teachers used symbolic representations rather than verbal
representations. No U.S. teachers used visual representations in solving the contextualized problem-solving
tasks.
On 21 of the 26 contextualized problem-solving tasks (81%), Chinese teachers used symbolic representations
in addition to verbal representations. Chinese teachers used verbal representations for only two of the tasks. On
the remaining three of the tasks, visual representations were also used in addition to using symbolic and verbal
representations. However, the visual representations themselves were not part of the solutions to these instructional
tasks in Chinese classrooms. Instead, Chinese teachers used them to facilitate students’ understanding of these tasks.
For example, in Mr. Xu’s second lesson, he continued to guide students to understanding the concept of percent through
word problem solving. One of the problems from the lesson illustrates this: A factory used 80 tons of water in September
and used 70 tons of water in October. What percent of water was used in October compared to September? What percent
more was used in September compared to October? What percent of water was saved compared to September? In the
discussion of this problem, Mr. Xu used the diagram shown below (see Fig. 2) to visually represent the amount of
water used in September, the amount of water used in October, and the amount of water saved in October compared to
September.