

Something to keep in mind with VEX is that they just split with the organization that runs all of their competitions, so there’s likely changes coming soon. Also, the company itself has had some… Culture issues, so I personally try to avoid using their products where possible.

Not just country but world now. Their K-8 program is a great entry into STEM as it is both an engineering challenge with the robot game and also the project that comes along with it (usually to design or organize around a certain challenge or theme).
FIRST also does a great job with their core values. They attempt to instill what they call Gracious Professionalism in everything that the program does. Basically, FIRST can be looked at as a program that tries to build good, competent people through the mechanism of a robot competition. In fact, the highest level award in the program is based around the impact that a team has on their community rather than how well a teams robot performs.
I might be a little biased, however, as I’ve been involved with the program (in the high school level competition) for about 17 years now. I know there are other programs out there that offer similar levels of STEM training, but none that build up people in the same fashion.