In terms of materials, the AAMC resources should be all you need. In addition to the old familiar classic stuff (FLs, QPacks, etc.), they recently released a CARS Diagnostic, which has ~28 passages and some guidance about how the CARS section is set up, and it's pretty helpful. This is probably less of a question of getting more materials, and more of a question of getting the most out of the ones you have.
First off, even more than usual, I'd emphasize focusing on AAMC materials over third-party materials here. RBT questions in particular are not very well-understood by third-party CARS writers. Per the AAMC itself, RBT questions focus on (1) extending passage opinions/perspectives to be applied to new contexts, or (2) evaluating new/hypothetical information and assessing how it relates to passage opinion/perspectives. They describe these skills as "application" and "integration," respectively, and view them explicitly as two sides of the same coin. The reason why I focus on this is that third-party resources instead often don't understand this, and instead write "RBT" questions that have more of a speculative feel and don't match the AAMC logic. So if you're running into this issue w/ third-party materials, don't stress it too much, and focus on the AAMC.
Once you're reviewing the AAMC materials, focus on understanding and internalizing the logic of correct vs. incorrect answer choices. Some common incorrect answer choice patterns you'll see for RBT questions are:
- Exaggerated opinions/perspectives (using too extreme wording)
- Answer choices that sound appealing to you, but don't line up with the perspective being asked about (either that of the author or someone else mentioned in the passage)
- Misattributed opinion/perspectives
- Excessively hypothetical reasoning (multiple leaps of logic)
- Answer choices that mix up cause and effect
- Irrelevant statements (i.e., choices that repeat passage information, but don't answer the question)
This isn't an exhaustive list, but should give you some sense of what to be on the lookout for. As you practice, look out for these patterns, and you'll eventually start to internalize what a correct answer to RBT questions feels like.
