The textbook is called MOSAIK and can be accessed online.
You will have to create an online account. Be sure to keep the email address and password handy.
The website to access the textbok is
Click on the correct book.
Blue Book - Level 1 for Intro to HS German and German 1A.
Green Book - Level 2 for Honors German 3
There are a number of excellent activities online that can be used to practice, whether or not they are assigned.