Problem-based learning encourages acquiring and applying new skills when working to solve a real life problem. Working on a real problem is practical and rewarding. It enables the learners to apply different learning strategies as well as to evaluate suitable information sources.
A problem that requires applying the skills you want to master or teach to others can be of great help for achieving your learning goals. Working together with your team to solve a problem can be very motivating and enforce skills for collaboration.
What kind of problem solving would help you to develop your knowledge in a topic you want to develop in?
What problem you can identify that is both useful to solve and requires improving the skills you want your team to practice