The Challenge Bank is one of our signature features. Essentially, it's a database of your missed questions across all practice tests. Every time you miss a question, it's added to your Challenge Bank automatically. Consider it your very own remediation room, another chance to retake those tricky questions and learn from your own mistakes.
We also use the Challenge Bank status to calculate your Pass Probability.
As a Premium subscriber, you're able to manually add questions to your Challenge Bank in case you want to work on them later. To do this, click the "Add this Question to Challenge Bank" link.
When the question is added, you'll notice that the counter on the Challenge Bank button in the sidebar will change.
Note: if the question you're trying to add is already in your Challenge Bank, it will not be added again and the counter on the button will not change.
Your Challenge Bank is available here: https://barprephero.com/challenge-bank/