Final answer:
The most effective first step for nurturing a new teacher's leadership skills is offering them various collaboration opportunities in school contexts.
Step-by-step explanation:
To nurture and expand a new teacher's leadership skills, the most appropriate and effective first step a principal can take is offering the new teacher opportunities to collaborate and contribute in a variety of school contexts. This approach allows the teacher to demonstrate and further develop leadership abilities in different scenarios and with diverse groups, fostering relationships and showcasing initiative. Additionally, it equips the new teacher with firsthand experience in schoolwide practices, policies, and culture, which can be essential for developing leadership within the school setting. Other approaches such as involving the teacher in low-level tasks or in reviewing professional literature, while beneficial in their own right, might not provide the same immediate and practical leadership development opportunities as active collaboration does.