I'm a university Professor in France and one of my courses is on 8-bit microcontroller programming.
In the past I used to use the 68HC05 as an example but for students who are not familiar with reading datasheets the investment in time was just huge. Although good and free simulators exist, these were hard for the students to find and install.
This book changed my student's life and considerably eased my life. The proposed microprocessor has all the features of a real one without the useless complexity drawbacks and heavy documentation. Students better like it than 68HC05 and there are plenty of examples that they can play with. A collection of slides for educators even avoids to have to compose your ones.
I highly recommend this as standard material for teaching microprocessor programming.