Google Design Challenge (Shortlisted)
A 7-day design challenge I worked right before graduation in 2020 on a mentorship application. The design prompt was:" Your school wants to strengthen the community by encouraging experienced students to connect with new students and help them adjust to campus life. Design an experience that allows mentors and mentees to discover each other. Consider the needs of both mentors and mentees, including how someone may become a mentor and how to connect mentors to mentees."

Learnings
Take your time. Understand this is about the process, not the result. The interviewer doesn’t expect you to come up with a perfect and polished solution.
Don’t start designing right away. This is a trap. The challenge will be very broad on purpose. The recruiter expects you to narrow it down. Start by asking questions. For example, if the problem is “design the perfect gifting experience,” you can ask: Who will be using this? What kind of gifts are we talking about? Who are they giving it to? How would they normally do it? What are the main pain points when giving a gift? Then, you can pick one of the pain points and start mocking up around it. Also, don’t assume the solution needs to be a mobile app. Think outside the box.
Be comfortable with uncertainty. You might get to a crossroad where two solutions are possible. Present both of them, list their pros and cons. and pick the one you think is best. You can always say that, ideally, you’d want to test them both, but for the sake of the exercise, you’re going with this one. Sometimes, it’s ok to move on even if you’re unsure.