Artificial intelligence (AI) has been considered a powerful tool for fostering language learning and applied to various language-learning contexts. Yet, language teachers might lack adequate knowledge about how to integrate AI into classrooms to facilitate students' learning effectively. To address the issue, this paper reports on an innovative practice to enhance secondary school students' creative writing by leveraging AI's capability for natural language generation (NLG). Specifically, we describe two learning designs for teaching students to write short stories with an AI-NLG writing tool ...