Some States require you to add a language for some years.
Some of our Core Programs and Just Good Books include language references and lessons and you can filter by this subject when adding these to your Family Learning Plan. A number of Simply Homeschool Core Programs include AUSLAN.
If you require something more structured, especially for high school, we suggest:
Duolingo - A Free App
Rosetta Stone - our favourite comprehensive language learning program. There are group discounts for Rosetta Stone available through some homeschooling groups and various other online outlets.