Re: Desperately need help
1. If students fail to pay outstanding fees, they are required to continue in the Elementary class and [a fine of? additional tuition of?] $2,000 will be imposed.
2. Students who did not achieve a minimum of 75% attendance will be barred from sitting (for) the examination. (Without the 'for' is very BrE). I don't think that 'bar' is the most common verb; 'not be allowed/permitted to sit' may be more usual.
3. Attached is a copy of the final examination question paper for our Elementary students. It has not yet been proofread.