Findings from the TIMSS 2019 Problem Solving and Inquiry Tasks

Ina V.S. Mullis, Michael O. Martin, Bethany Fishbein, Pierre Foy, and Sebastian Moncaleano

Chapter 2: Science Grade 4

Farm Investigation

Screen 12 – Microscope

On Screen 12, George uses the microscope to examine a cow hair and a goat hair. Students are asked to move the slider to make the images as clear as possible.

In 12A, students adjust the slider to make the cow hair as clear as possible, and in 12B to make the goat hair as clear as possible. Students were awarded credit (1 point) for correctly positioning the slider for both animal hairs.

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Maximum Score Points: 1
Content Domain: Life Science
Topic Area: Characteristics and Life Processes of Organisms
Cognitive Domain: Knowing
Science Practice: Generating Evidence


Positioning the microscope slider is a relatively straightforward task, which students performed reasonably well, shown in Exhibit 24. On average internationally, two-thirds of the students (66%) focused the microscope correctly on both animal hairs. In general, focusing the microscope was something the students were able to do for both hairs or not at all. Only 4 percent on average were able to focus on the cow hair but not the goat hair, and just 8 percent on the goat hair but not the cow hair. There was little difference between girls and boys in performance on this item.