Creating authentic science assessments that engage students in conceptual understanding and provide evidence of their learning is challenging. Student-centered instruction and assessments provide an opportunity to build student agency and foster positive student relations with science. This qualitative work showcases assessments that focus on knowledge-in-use and assessments that incorporate opportunities for and evidence of student learning. We present the design, implementation, and reception of two authentic assessments, Science Portfolios and Teaching Presentations, designed for and implemented in an interdisciplinary science content course for preservice K-8 educators. Each assessment was designed to deepen student knowledge and incorporate relevance to students' future careers as teachers. These science assessments created authentic opportunities for, and served as evidence of, student learning. We offer our reflections about the implementation and discuss how these types of assessments could be used in other science classrooms.