StemBox is recommended for ages 7-12 years old.
At 7-8 years old children have the basic motor and cognitive levels necessary to complete a box on their own but we highly recommend parent involvement. Videos on the website can be very helpful for mimicry to complete the experiment.
At 9-10 years old children should be able to complete a box on their own without adult help (unless specified in the instruction manual). Resources on the box resources page for that box can provide additional websites to learn more about the topics.
At 11-12 years old children are capable of not only completing the box on their own without adult help (unless specified in the instruction manual), but they are capable and encouraged to devise new variables and experiments for each box. The box resources page for that box is a great way to identify a future career path and next steps for pursuing this field.