Assigning grades is probably the most important measurement decision that classroom teachers makes. When teachers are provided with some measurement instruction, they still use subjective value judgments when assigning grades to students. This paper therefore, examines the grading practice as valid measures of academic achievement in secondary schools student for national development. Three hundred teachers (300) were sampled by means of stratified random sampling techniques from the three senatorial districts in Delta State. A validated questionnaire was used for data collection. Mean and standard deviation was used to answer the research questions while t-test statistic was used to test the stated hypotheses at 0.05 level of significance. The results of the study revealed that there was no significant difference between male and female teachers grading of students in secondary schools; there was significant difference between urban and rural teachers assigning of grades to students work accurately in secondary schools in Delta State.