Duolingo announced that it will launch new math and music learning programs as the latest addition to its language-learning platform.

Duolingo's free music course is meant to help make learning music more accessible, with professional lessons costing up to $400 per lesson.

When learning to count by eight, the bestselling musician might not immediately come to mind, but teacher Faith McPeek used Swift's famous music to create a memorable teaching rhyme.

Duolingo is best known for its language learning app, but it recently branched into teaching math and will soon offer music lessons.

Last October, it debuted Duolingo Math, which was its first broader subject expansion beyond language learning. Duolingo Music and the multi-subject experience in the new app will be fully ...