Here's another Explora program that might be of interest, although it's not specifically geared toward homeschoolers.  It's an afterschool program called Robo Task Force.  Here's a description and a link.  Sounds really cool.

"Robo Task Force is an after-school robotics club that offers transactive experiences for 3rd through 7th graders. Join other participants in exploring construction, materials development, electronics principles and robotic systems and design."

[url]http://www.explora.us/en/mn-educational-programs-en/mn-after-school-clubs-en
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