PBS has some great resources for social studies. Simply type in the topic (for example - Maya) and several suggestions/hits will come up. Please review the results with your child to make sure it is suitable and relevant.
Ten minute summary of the day's top/interesting news stories, rewritten for students. The site recommends an adult previews each segment before children watch in case there is any objectionable material. Great for increasing students' background knowledge.
This site allows students to practice vocabulary while earning rice for people in need, at no cost to you. Check it out, anyone can play! Besides vocabulary, students can improve their skills in other subjects, too.
This site provides leveled texts of nonfiction news articles, and allows students to choose the level they feel comfortable at reading. Quizzes for articles are available too, and students are encouraged to take the quizzes as it helps provide feedback on students' needs.