Click around on the image below to find activities you can do to practice German or learn about some German culture!
DuoLingo: German 1, German 2, German 3
The classes allow me to see what you're doing, and to potentially make "assignments".
Deutschtrainer A1/A2 from Goethe Institut
You can search for the app in different levels. A1 would be good for German 1 or as a review for anybody. German 2-3 could try A2.