Within ScholarPack you can add a standard header in areas such as Admin > Students > Attendance Letters.
This header will take the information from Admin > Config > Core Set Up > School for the school name and address and if a logo is present in Admin > Config > Core Set Up > Images it will pull this through.
Alternatively if you have a specific school header we would suggest printing the letters on headed paper or adding a header within Word once the letter is exported.