The link in the article has more detail[0], which includes an expanded "critical thinking" section. Also from the comments on that page, from one of the authors

The link in the article has more detail[0], which includes an expanded "critical thinking" section. Also from the comments on that page, from one of the authors: "...separate articles focused on each of the outcomes described here are currently under review at journals. This is a summary of the combined results". [0] http://educationnext.org/the-educational-value-of-field-trips http://educationnext.org/the-educational-value-of-field-trip...