Niedersachsen
Parents have the choice between a public school or a private school. For enrollment, the children must be registered at the primary school responsible in the school district where the child is resident. (https://www.mk.niedersachsen.de/startseite/schule/unsere_schulen/allgemein_bildende_schulen/grundschule/vor_einschulung/vor-der-schule-149343.html).
After attending the primary school, the guardians decide which secondary school form their child should attend. Prior to the decision, the primary school offers at least two consultations in class 4, in order to inform about the individual learning development of the child and to advise on the choice of secondary school types (https://www.mk.niedersachsen.de/startseite/schule/unsere_schulen/allgemein_bildende_schulen/grundschule/uebergang_von_grundschule_auf_eine_weiterfuehrende_schule/Uebergang+Grundschule+weiterfuehrende+Schule-5842.html).