The Frisian languages are a closely related group of West Germanic languages, spoken by about 400,000 people, who live on the southern fringes of the North Sea in the Netherlands and Germany.

Although Frisian is linguistically close to English and German the languages are not mutually intelligible. For L2 speakers, both the quality and amount of time Frisian is taught in the classroom is low, concluding that Frisian lessons do not contribute meaningfully to the linguistic and cultural development of the students. Moreover, Frisian runs the risk of dissolving into Dutch, especially in Friesland, where both languages are used.

Only 30% of the West Frisian population are competent in the language. It went out of use in the 16th century and continues to be barely taught today.

Though North Frisian has no official status in Germany, it is occasionally used at local council meetings, etc. A few villages have Frisian road signs and bilingual place names are allowed. Frisian house names are popular, particularly on the islands where Frisian is spoken. The language is taught for a couple of hours a week in schools and there are a number of Frisian courses for adults throughout the region. There are regular, short broadcasts in Frisian on the radio, occasional Frisian articles in the German newspapers, and some Frisian literature, theatre and choirs.

Sources:
Wikipedia
Omniglot