The purpose of this study was to investigate if there are any significant differences in the mathematical attainment of pupils' grade one of primary school in Makkah, Kingdom of Saudi Arabia (K.S.A) between those pupils who had attended kindergarten and their peers who had not, and whether this effect continued into the second and third grades in mathematics attainment. Also the study aimed to investigate the role that teachers' expectation for their students' achievement might play in accounting for any differences. This study was limited to 685 primary fourth grades pupils (special need not include) who had progressed through the first, second and third grades of the primary school in the city of Makkah (K.S.A) in the academic year of 2002-2003 drawn from the 40 primary schools, randomly selected from the four areas in the city of Makkah (North, South, East, and West of Makkah) 20 schools for boys and 20 schools for girls. 417 of pupils sample had attended kindergarten (294 boys and 123 girls) and 268 of pupils had not (106 boys and 162 girls). Two main methods of data collection were used in this study: a) mathematical scores of final exam the total mathematical scores that the pupils had achieved in the three grades (first grade 1999, second grade 2000, and third grade 2001) were collected from the administration office of each of the schools, and b) teachers' questionnaire consisted of questions to elicit information on the teachers' view about the importance of kindergarten education, as well as their view about the academic and social adjustment differences, if any, between primary school pupils with kindergarten education background and their peers without such an experience. The result of the study indicated that: (1) the pupils who had attended kindergarten significantly out-performed their peers who had not attended kindergarten in the first grade and the effect was continued in the second and third grades; (2) the gender of pupils who had attended kindergarten did not affect mathematical attainment in the three grades of primary school, although the girls who had not attended kindergarten were better than the boys. This trend of the impact of kindergarten education on mathematics achievement at the early primary school level was corroborated by the opinions of the primary school teachers, who concurred with the notion of the positive effect of kindergarten education on its recipients. Finally the results concluded that there is a strong indication that attending kindergarten has been shown to be effective in supporting the mathematical education of primary age children If this is so, then it appears to us that all children should attend kindergarten before joining primary school, therefore, it is recommended that Saudi Arabian government should work towards universalizing kindergarten education. Integrating kindergarten education into the current basic education could do this. Appended are: (1) tabular data; (2) open-ended questionnaire; and (3) close-ended questionnaire. (Contains 11 tables.)