In this brief, authors Namsoo Shin, Kevin Haudek, and Joseph Krajcik explore how artificial intelligence (AI) can serve as a transformative learning partner in K-12 STEM education. They describe theoretical foundations of using AI in STEM education and the importance of fostering an integrated understanding of STEM content. The brief examines AI's potential to offer personalized support, scaffold cognitive and metacognitive processes, and enhance student motivation and collaboration. Additionally, the authors consider how AI can promote access to STEM learning, while also addressing the need to identify and mitigate biases in AI system development to ensure broad and effective application.