Respected Sir/ Madam,
I would like to inform you that my name is __________ (name) and I am a student of _________ (mention class/ department) of your reputed school/ college. My roll number is _________ (mention your roll number).
I write this email in order to bring to your kind consideration that I ____________ (mention reason – am not well/ out of town/ any other) due to which I will not be able to attend the classes for ______ (number of days) day/ days from __/__/____ (date) till __/__/____ (date).
I request you to kindly approve my leave. I shall be highly thankful for your kind support.
– Regards.
_________ (name),
_________ (roll number),
_________ (contact details)