As you are aware that the Board has prescribed pass criteria for Class IX & XI in the Examination Bye-Laws of CBSE and the same is as under:-
Rule 40.1(vi) “in order to be declared as having passed the Class XI Examination a candidate shall obtain 33% marks in all the subjects. The pass marks in each subject of examination shall be 33%. In case of subject involving practical work a candidate must obtain 33% marks in theory and 33% in practical separately in addition to 33% marks in aggregate in order to qualify in that subject.”
Rule 41.1(vi) “in order to be declared as having passed in Class IX Examination a candidate shall obtain 33% marks in all the subjects. The pass marks in each subject of examination shall be 33%.
Some schools are reportedly framing their own pass criterion which leads to detention of a large number of students in Class XI and Class IX. This practice is strictly against the laws laid by the CBSE and shall be reported to them.