Britannica has articles, videos and images about topics including Science, Art, Biography and just about anything you need for your school reports.
At the Britannica website type a keyword into the search bar at the top of the page. You can choose to read about your topic at Level 1 for first, second and third graders; and level 2 for fourth and fifth graders. Have fun there are lots of video clips to see and images to choose from.