A thread for bumping up, for information, so we don't have to keep repeating ourselves.
You'll find a sample de-registration letter (England and Wales) and other information about the realities and legalities of home education on the Education Otherwise and Home Education UKwebsites.
It is recommended that you get a receipt for the letter.
You are not obliged to have any further contact with the school once they have received this letter.
You are not obliged to contact the LA yourself at all, that is the school's responsibility.
Note that if you were already being pursued for truancy, that offence still stands but your child cannot be a truant if they are not a registered pupil. If you are providing an education under s7 of the Education Act 1996 by the time it gets to court, you may be fined for the earlier truancy but it seems unlikely a court would order a parent to prison.
For information about home education in Scotland contact Schoolhouse