Enough "I" statements already. It's ironic how many people seem to think their personal experience is somehow relevant on a post about "critical thinking."

The ONLY sane way to answer these questions: - Does math increase critical thinking? - Does critical thinking lead to more career earnings/happiness/etc? - When does math education increase critical thinking most? - What kind of math education increases critical thinking?

Is with a large-scale research study that defines an objective way to measure critical thinking and controls for relevant variables.

Meaning you don't get an anecdotal opinion on the matter on your study-of-1 no-control-group no-objective-measure personal experience.