Mathematics is utmost important for the daily life of the people. It is one of the significant subjects which improve the abilities and skills in a variety of calculations. Learning mathematical skills at the secondary level is highly emphasized because it will help the cognitive skills of the children. This is an experimental study using single group pretest treatment post test design. The major objectives of the study wereto diagnose the mathematical performance of Grade 08 students who are identified to be improved, and to assess the efficacy of Metacognitive and Neurocognitive Intervention strategies in enhancing mathematical performance of Grade 08 students. For this study, a sample of 35 Grade 08 Students studying at AK/Al-Muneera Girls High Schools, Addalaichenai who were identified poor in proficiency in mathematic ability was selected by using purposive sampling technique. Data were collected using Mathametic Achievement Tests (Diagnostic Test, Pretest, Post test, and Progressive Test) and Observation Sheet: The findings of the study have revealed that Metacognitive and Neurocognitive Intervention Strategies were effective in enhancing mathematical achievement of students.