Investigation of the relationship between non-verbal intelligence levels and academic achievement in mathematics among gifted students

The aim of this research is to examine the relationship between the non-verbal intelligence levels and the academic achievement in mathematics of gifted students. A descriptive research model was employed in this study. Two different sample groups were selected for the research. The first sample group was determined for the validity and reliability study of the TONI-3 test at the 9th-grade level. The second sample group was chosen to investigate the non-verbal intelligence levels and academic achievement in mathematics of gifted students. The sample group of our study consists of 9th-grade students from a total of 11 institutions in İzmir, including three science and art centers, one science high school, three Anatolian high schools, two vocational and technical Anatolian high schools, and two schools providing education for students with special needs. Single screening and correlational models were used for data collection. In the reliability analyses of the TONI-3, the Cronbach Alpha for the TONI-3 test was found to be .96, Spearman-Brown (p) .97, parallel form .71, test-retest .74, and Guttman .97. Regarding the validity of the TONI-3 test, a moderate positive correlation of .58 was found between the TONI-3 and RPM, and a high positive correlation of .83 was found between the TONI-3 and mathematics written exam scores. Non-verbal intelligence levels according to school type were analyzed with ANOVA. It was found that students attending science high schools and science and art centers had significantly higher scores on the TONI-3 non-verbal intelligence test compared to other school types, but the scores of science high school and BİLSEM students were similar. The variability in non-verbal intelligence levels of individuals was explained by 34% by the school type variable. The differences in the number of correct answers in LGS Mathematics according to school type were analyzed with ANOVA, and it was found that 76% of the variability in mathematics scores was explained by the school type variable. A moderate, positive, and significant relationship was found between the TONI-3 and LGS success. The differences in LGS mathematics achievement and TONI-3 non-verbal intelligence test results between gifted and typically developing students were examined using the t-test, and it was found that the mathematics LGS scores and TONI-3 non-verbal intelligence test results of gifted individuals were significantly higher than those of typically developing students. The findings indicate that the TONI-3 Non-Verbal Intelligence test is a valid and reliable intelligence test for 9th-grade students. The results of the analyses show that there is a relationship between the non-verbal intelligence levels of gifted students and their academic achievement in mathematics. Keywords: TONI-3, Non-verbal intelligence level, Academic achievement level, Giftedness, Intelligence.