This is the 9961st most frequent Korean word.
공모전은
A "contest" or "competition."
Here, '공모전은' is the subject indicating that competitions (공모전) are the topic being described as a good opportunity.
공모전은 창의력을 발휘할 좋은 기회입니다.
Competitions are a great opportunity to showcase creativity.
In this sentence, '공모전은' refers to a specific competition happening this time (이번), and it specifies the topic of discussion.
이번 공모전은 주제가 독특해서 많은 관심을 받고 있습니다.
This competition is receiving a lot of attention because its theme is unique.
Here, '공모전은' is used as the subject in a reported thought to express students' opinions about competitions being significant events.