Abstract: A computer-implemented training system includes data storage storing: (i) a first set of visual instruction materials, (ii) a second set of audio instruction materials, and (iii) a set of user data. The user data includes, for each user, (a) a first indication of a visual instruction status and (b) a second indication of an audio instruction status. Also stored is a presentation control processing arrangement configured for selecting an instruction material of the first set or the second set and causing it to be presented to a user. The presentation control processing arrangement is configured to, for a specific user, select one of (a) a visual instruction material from the first set based on the first indication for that user and (b) an audio instruction material from the second set based on the second indication for that user, and presenting the selected instruction material to the user.