Chiu Lut Sau Memorial Secondary School , or CLSMSS in short, is a secondary school in Yuen Long, Hong Kong. It was founded in 1979. It is a Band 1 school and is one of the 14 Government schools approved for using English as the medium of instruction for all levels.The school's mission is to provide students with a balanced education aimed at excellence in moral, intellectual, physical, interpersonal and aesthetic development and at fulfillment of the school motto - Wisdom, Virtue, Honesty and Progress, whereby they can achieve self-actualization in all respects throughout their lives and as leaders of tomorrow.Lut Sau HallLut Sau Hall is the official school hall of the school. In the past, it was also used as a local community hall for cultural performances. In early 2000s, the state of community hall was ended after the opening of Yuen Long Theatre near the school.Class SystemThe school has approximately 200 students in each year from S1 to S6. Students are divided into 5 classes A, B, C, D, E according to their academic performance, with A and B being the better classes in junior form(F1-F3).In Senior form, there would be classes according to the preferences of students in choosing the electives. Remedial lessons are also arranged to give support to students of lower ability.Medium of InstructionExcept Chinese subjects, cultural subjects and Civic Education and Liberal Studies, English is used in learning and teaching in all subjects.House systemStudents are divided into four houses, comprising members of all the classes in the school. The houses are named Wisdom, Virtue, Honesty, and Progress. The houses compete against each other in the annual Swimming Gala and Athletics Meet.