ACT-R is a complete cognitive model that incorporates Working Memory, Declarative Memory and Procedural Memory, but also incorporates input (visual and auditory) and output (manual) buffers. It is a really interesting model about the human in its entirety but, it is at a high level of abstraction.
The paper about memory you want is "REFLECTIONS OF THE
ENVIRONMENT IN MEMORY" by Schooler and Anderson. It describes how and why memory is like Reïnforcement learning. In this paper you can read how memory is used for studying. About learning to leverage the working memory, I don't exactly know what you mean, but I think these papers give you a nice headstart.
If you want to learn more about ACT-R, I would recommend this book, or just read the many papers they have published over the years. They have great examples that explain multitasking and time perception among others.