Science in the Classroom (SitC) is a collection of freely available annotated research papers from the Science family of journals. SitC aims to help educators, undergraduates, and advanced high school students understand the research contained in scientific primary literature by using annotations and providing accompanying teaching materials. Annotations include vocabulary, methods, descriptions of prior research, and explanations of major conclusions. Each paper has an educator's guide outlining connections to science competencies within STEM learning frameworks and standards. Educator guides also provide suggested activities, discussion questions, and resources for further exploration of the subject.