Introduce the idea of spin as analogue to classical angular momentum, and offer an equation for the magnetic moment from this spin that they need to ‘trust’ for now based on the form for the classical magnetic moment.
Motivate that the equation for the magnetic moment a good starting point because we do see deflection – so there is some similarity.
But there is no reason to expect same factor out front – so can introduce g-factor, and bring in real-world data and exposure to research topics.
(There is a supplementary document provided that gives the main historic points of the experiment, discusses spin, and the g-factor)
Discuss carefully that Spin is NOT rotation, and that it is intrinsic – this will need to be repeated many times throughout the course.