This study investigated the change of the science academic achievement by grade level and gender where 222 elementary students' science and technology course scores between the 4th and 8th grades and science success percentages in 6th and 8th grades Level Determination Exam were longitudinally analyzed. Based on the findings of this study, consistent with the results of the national achievement tests, a significant decrease was observed in elementary students' science academic achievement as their grade level increased. From the analysis of the changes in science academic achievement by gender, a significant difference between the 4-8th grade science scores was found out. Based on the comparisons for each grade level, girls were consistently found to have at least slightly higher science success than boys; furthermore, it was observed that this difference became statistically significant as the grade level increased. In light of the findings of this study, recommendations were listed for enhancing the low science academic achievement of elementary students, and about closing the gap between genders, which was emphasized among the goals of the new science and technology teaching program.