This symposium at SREE 2025 examines new approaches to assessing how young children learn science and engineering in the early grades. Presenters will share a landscape analysis of existing assessments and introduce innovative tools, including computer-adaptive tests, game-based performance tasks, and measures of computational thinking. Together, these studies highlight both the promise and the challenges of developing developmentally appropriate assessments that capture the richness of children’s emerging skills and align with the Next Generation Science Standards.