Did you know that National Geographic Explorer magazines can be accessed for free? It's true! Issues from September 2009 are available in projectable editions and also include access to the teacher's guide. The most exciting thing about the explorer magazine is that it comes in two reading levels. This way, your struggling upper grade students can have access to the same ideas as your proficient readers. The Pioneer edition is the lower reading level, probably best suited for later second grade readers or third grade readers and up. The Pathfinder edition is the upper reading level, probably suited for higher fourth grade readers and up. Give them both a look here and see which will be best for your students. You can also print the articles or entire magazine edition from the projectable view. I subscribed to the two editions when I taught 5th grade and loved that all of the students in my class could access the information, regardless of reading level. I'd love to know how you use this in your classroom in the comments below or any other resources like this you use in your classroom.