Saarland
The legal guardians enrol their child orally or in writing at the primary school responsible in the school district where the child is resident. The registration must be made within the deadline set for this purpose (§ 2 (1) General School Regulations Saarland). As a rule, parents receive a letter from the school administration about ten to eleven months before the start of school, indicating the relevant primary school and the registration period.
Registration in secondary schools is made by the parents or guardians within a period of time specified by the school inspectorate, which will be announced in due time. When registering, the mid-term certificate of grade 4 should be submitted along with the development report (§ 2 (1) admission regulation, http://sl.juris.de/cgi-bin/landesrecht.py?d=http://sl.juris.de/sl/gesamt/Sek1AufnV_SL.htm).
Dates for school registration can be found at https://www.saarland.de/173569.htm