Many STEM teachers have taken advantage of the free and easy to use visual programming languages in their classrooms with applications such as Alice and Scratch. These programming tools allow students to create all sorts of functions, graphics and games using simple snap together blocks that teach students the fundamentals of writing computer programs. As your students move on to more advanced (and more marketable) languages such as Javascript, XML and Python, the task becomes a bit more difficult to teach because students have to deal strictly with handwritten code. Google Blockly is a promising way to transition student from the Scratch-style environment to handwritten code. Students can write programs using snap together blocks as with Scratch and Alice, but with Blockly you can export the blocks into your choice of Javascript, Dart, Python and XML. This allow students to move back and forth easily between program and programming styles to see instantly how changes in blocks transfer into their choice of code. Blocks include Control, Logic, Math, Text, Lists, Variables and Procedures so a wide variety of advanced functionality can be accessed.  A very simple introduction is provided with a maze that must be navigated using Blockly. Its a lot of fun and numerous mazes are available which students love to solve and quickly forget that they are indeed engaged in computer science. Principles of computer programming have application is multiple STEM areas, and you can’t go wrong giving this one a good hard look and use it in the coming year.