This study investigates time allocation and time use in mathematics and science classes in Newfoundland and Labrador high schools. 1: examines how much time is allocated for instruction in these courses, how much of this allocated time is actually used for instruction, and if the time allocation can be associated with achievement in mathematics and science courses. -- Using self-reporting surveys administered to teachers and university students, it was found that approximately 75 percent of allocated instructional time in mathematics and science is used for instruction. The remaining time is used for non-instructional activities such as examinations and extra-curricular activities. There are also days in which no instruction occurs because of weather, teacher workshops or student absenteeism. The achievement data used in this study were compiled from the available data base supplied by the Government of Newfoundland and Labrador. -- The correlation coefficients completed revealed that there are some weak, positive relationships between time allocations and achievement in mathematics and science courses at both the school level and the student level. Regression analysis done on the student data indicated the time variable can be used to explain variation in student achievement for university level mathematics and science courses.