In schools in Nordrhein-Westfalen, the voluntary additional instruction in the language of origin is an offer for students who grow up bilingual or multilingual. Further information can be found at https://www.schulministerium.nrw.de/docs/Schulsystem/Unterricht/Lernbereiche-und-Faecher/Herkunftssprachlicher-Unterricht/
The group size for instruction is set to at least 15 pupils in primary school and at least 18 students in lower secondary school. Mother tongue lessons take place usually up to five hours per week. At the end of mother tongue teaching according to Class 9 or 10, a language examination can be taken (https://www.schulministerium.nrw.de/docs/Schulsystem/Unterricht/Lernbereiche-und-Faecher/Herkunftssprachlicher-Unterricht/FAQ-Sprachfeststellungspruefung/index.html).
In recent years examinations took place in the following languages:
Albanian, Arabic, Chinese, Greek, Italian, Croatian, Persian, Polish, Portuguese, Romanian, Russian, Serbian, Spanish, Czech, Turkish, Hungarian, Vietnamese. If suitable examiners are available and the organizational conditions permit, other languages can also be examined.