Mathematics is an important branch of cognition and the increase of mathematical thinking is a fundamental pillar in the orientation of educational development within a new, advanced educational system. It is in the nature of a person or student to think, and thinking promoted across a range of disciplines is practised in our schools through education. Therefore, day by day, a sense of the significance of thinking in the educational field usually and more particularly in specific disciplines has developed among educators. Learning how to think mathematically is an extremely important issue in mathematics education. This study is examined towards the mathematics achievement and mental ability among higher secondary school students. It was administered to 768 higher secondary first year students. Differences were compared for type of family and parental education. Results indicated that students from nuclear family scored more than the student from the joint family regarding mathematics achievement and mental ability. But in the case of parental education student of college education as parental education scored more than the other secondary and higher secondary regarding mathematics achievement and Mental Ability do not have significant difference towards higher secondary first year higher than others.