The relationship between attention and academic performance has been of interest starting with early studies on academic success and failure. In this study we examine how attention measured in simple and prolonged over-learned response tasks correlates with and contributes to scientific reasoning and school achievement (GPA). To study attention the Attention Concentration Test (ACT) was used and to study scientific reasoning, a modified version of Science Reasoning Tasks, tapping control-of-variable schemata, was used. Of special interest were the highest performing attention group (+ 1 SD) formed from the ACT results. We gathered our data from Finnish ninth graders (n = 358; including 166 girls) from the city located eastern part of the Finland. Statistically analysed results showed that attention contributed to scientific reasoning, which in turn explained the largest share of the GPA variance. The highest attention group differed from the lowest two attention groups in GPA and from all attention groups in scientific reasoning. For educational practitioners the ACT seems to be a useful tool in assessing exceptional academic learning potential in students.