The main objective of this study was to determine the effectiveness of teacher`s classroom practices on the learner`s apprehension in mathematics of Grade 11 students of Laguna State polytechnic-Santa. Cruz Campus, School Year 2022-2023. It sought to answer the following questions: (1) What is the level of Classroom Practices in terms of Classroom Management, Teaching Styles, Instruction, and Assessment; (2) What is the level of Learners’ Apprehension in Mathematics with regards to Individual Participation; and Group Participation; (3) What is the level of learners’ performance relative to general weighted average; (4) Is there a significant effect of Classroom Practices on the Learners’ Apprehension in Mathematics; (5) Is there a significant effect of Classroom Practices on the Learners’ Performance in Mathematics; The research design utilized in this study was Descriptive Research Design. This research method is used for frequencies, averages and other statistical calculations. The subject was observed in a completely natural and unchanged natural environment. It is often used as a pre-cursor to quantitative research designs, the general overview giving some valuable pointers as to what variables are worth testing quantitatively. Characteristics of this method can determine if traditional classroom practices affect the apprehension of learners towards mathematics. Information gathered will be used in order to test hypothesis concerning the current status of the study. Findings revealed that the teacher`s classroom practices evaluated by students was high in terms of classroom management, teaching style and instruction while assessment was very high. Learner`s apprehension by the students was high in terms of individual participation while group participation was moderate. The level of learners’ performance relative to general weighted average was equivalent to outstanding. It was found that there was no significant effect of classroom practices on the Learners’ Apprehension in Mathematics in terms of group participation while in individual participation there was a significant effect with regards to classroom management. It was also found that there was no significant effect of classroom practices on the Learners’ Performance in Mathematics in terms of General weighted average. Since the classroom management in terms of individual participation was significant therefore the hypothesis stated that there is no significant effect of classroom practices on the learners’ apprehension of mathematics was partially accepted. However, the significant effect of classroom practices on the learners’ performance in mathematics indicated that the null hypothesis was accepted. This study suggested that teacher classroom practices do not affect learner apprehension and performance in Mathematics in terms of group participation. It was suggested that exploring other variables that affect apprehension and performance, as classroom management affects individual participation. Teachers should take actions to create a successful learning environment, positively impacting students' achievement of learning requirements and goals.