School are not obliged to offer mother tongue instruction.
The Berlin Education Act allows schools to offer pupils of non-German language of origin mother tongue teaching. The schools can use the offers of third parties (§ 15 Abs. 3 Education Act Berlin). At present, mother tongue supplementary teaching (MEU) is offered by diplomatic missions in the form of so-called consular education, mostly in Turkish, but also in Portuguese, Italian, Macedonian and Serbian.
Either elementary and secondary schools in Berlin offer bilingual instruction:
Schulen, die bilingualen Unterricht in Deutsch-Englisch anbieten
Schulen, die bilingualen Unterricht in Deutsch-Französisch anbieten
Schulen, die bilingualen Unterricht in Deutsch-Spanisch anbieten
In elementary and secondary schools of the “Staatliche Europa-Schulen Berlin” (SESB) bilingual instruction in nine language combinations is offered: German-English, German-French, German-Greek, German-Italian, German-Polish, German-Portuguese, German-Russian, German-Spanish and German-Turkish (http://www.berlin.de/sen/bildung/schule/besondere-schulangebote/staatliche-europaschule/).