Central Board Of Secondary Education [CBSE] — Mathematics class 10

Hello sir,
I'm studying in class 10 of Chinmaya vidyalaya kannamaly, kochi
I'm writing this letter because our school is forcing students to choose only standard maths and not basic...many of the students are facing difficulties...our school is only trying to protect their popularity but not helping students...we as students face many difficulties in mathematics but we cannot choose basic maths...I request your help as soon as possible because our preboards are being conducted now and we are begging to take basic but we are not been allowed