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 4: Science Grade 8

Pepper Plants

Screen 11 – Evaluate an Example Experimental Setup

Screen 11 displays the results of a correct experimental setup, providing all students with the opportunity to interpret the same data. Correct responses indicated that the graph showed fertilizer helped pepper plant production because both tanks with fertilizer produced more flowers (and consequently would produce more peppers) than the tank with no fertilizer.

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Maximum Score Points: 1
Content Domain: Biology
Topic Area: Life Cycles, Reproduction, and Heredity
Cognitive Domain: Applying
Science Practice: Working with Data


Exhibit 52 shows the average percent correct across countries was 21 percent. Some of the explanations judged incorrect did include information from the graph. For example, 5 percent on average mentioned the two tanks with flowers but not the third tank, and a few, 2 percent on average, mentioned the height of the plants. In general, however, the eighth grade students had difficulty evaluating the results shown in the graph. Girls outperformed boys on average across countries.