We've seen several 2D pixel art creators like Pixilart and even a site just for creating pixel art you can put on your wall called Stickaz, but I haven't played with an in-browser 3D pixel art app. If you have access to a 3D printer, you can print them or fold them into adorable paper figurines:
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scott.little@gnspes.ca Please help Thanks!
Pros:We loved the program at our school, but can not get it anymore
Cons:It does not work! many of my students had made and saved work to voxelbuilder and the link is gone. We used to use buildbuildermr dube.