Snap! - is a versatile programming language created at University of California, Berkeley. The Infusing Computing team at NCSU likes the functionality of it for students, as it is similar to other platforms.
Scratch - created by MIT for students, and links and sample teacher lessons.
Approved by Wake County in the LearnPlatform.
Within the Code.org site, you'll find several block-based programs like Flixter, along with HTML, CSS, and JavaScript.
Use Robots like Sphero and Dash and Dot as well!
Approved by Wake County in the LearnPlatform.
NetsBlox by Vanderbilt University and sponsored by the National Science Foundation is another platform for students. They have good examples of student work, too!