Discovery for Education has many free resources for teachers. Once you are logged in, you can search by subject, grade, and topic to find materials for your class.
PBS Learning Media is a great resource for many different types of tools (images, videos, documents, activities, interactives, lesson plans, etc.) You can search by topic, subject and grade level.
Annenberg's Learner.org Website was recommended during the HRS trainings. In addition to professional development, you can search for lessons and interactives by subject then grade level.
Wonderopolis is one of my favorite websites! It provides many of the essential parts of PBL Activities. You can sign up for the Wonder of the Day for a daily topic of discussion (perfect for journal writing.)
PhET Interactive Simulations is provided by University of Colorado Bouldin. Once you select Play with Simulations, you can search for activities based on grade level.
Great Website for Kids is provided by the Association for Library Service for Children a division of the American Library Association.
Eric Curts continually updates this list of online Science resources and provides it free for everyone!
🔬 Tech Integration Updates - Science and STEM
Interactive Sites for Education is provided by Karen Ogen. Sites are searchable by topic within each subject. Karen has other resources available on her Blog.