He encouraged his students to not only study the pens and their shapes, but also adopt a critical view on making digital tools (and doing the math).
His book The Stroke has been translated in (amongst others) English, German, French, Italian, Spanish, Portuguese, Korean, Croatian and Russian.
Noordzij introduced his own method of teaching typography and type design at the Royal Academy of Art, based on his theoretical system ′The stroke of the pen′.
He presented this system in a booklet called The stroke of the pen: fundamental aspects of western writing (1982), and further developed it in the Dutch booklet De Streek: Theorie van het schrift (1985) (which was translated to English in 2005, called The Stroke: Theory of Writing).
Even though this theoretical model mostly concerns the written word, Noordzij applies it to printed type as well, as he defines typography as ′writing with prefabricated characters′.
[2][3] The method of teaching type design at the Royal Academy is still largely based on Noordzij's theoretical model today, as several of his former students are now the professors at the department.