Not necessarily, because everything is on screen, meaning that, ideally, music stands and books can be dispensed with completely, as long as everyone can see the screen clearly.
However, the books can make lessons much more productive – one of the challenges of whole class brass teaching is that there are times when one group of instruments will need to play on its own, and students with different instrument types can become bored and distracted if they have nothing to do during this time. The books allow them to follow their own parts, while the screen is displaying the parts for other instruments.
In addition, the 2nd year of the course will reuse some of the tunes from year 1, but with more advanced arrangements. If new students have joined the class, they can be given the simpler version of the music from the year 1 books, while the other students read from the screen, or their year 2 books, meaning that beginners are not left out.
Lastly, the books are useful for all students to practise with at home.
Each year of the course has a book for treble clef instruments, plus another for bass clef, both containing all the written material from the website that is relevant to their instruments. The books are A5 size in order to fit easily into most brass instrument cases. Of course, the website will still need to be used for the backing tracks.
The books can be bought here.