I'm intrigued by a the discussion of academic rigor, and I think our experience homeschooling our oldest daughter might shed some light on this subject. This is a draft of my thinking:
The dialog around academic rigor often feels as if it is based on the two opposing, but exclusive, viewpoints, between which we are asked to choose: 1) the environment which emphasizes passion, or 2) the environment that focuses on rigor. (The former being seen as "loose," and the latter often being the rationale for high-stakes testing.)
And just stopping here, I think there are many that would agree that the two should not be mutually exclusive. But even then, there is still an inherent assumption to the discussion that I want to challenge: either or both are almost always presented in the structure of our traditional school system--that is, where education is something that adults impose upon children.
Now, before you write me off as being flaky or weird, here is the alternative assumption: that education is essential to the health and well-being of ourselves as individuals, and when we are rigorously engaged in our own life learning, we can generatively mentor students by communicating the value of being both passionate and rigorous, and expecting both. And it is amazing to find that when education is treated this holistically, students can accomplish incredible things. We're all aware of students who have done this, we just don't see it as the norm (which is part of the problem).
In the homeschool program our daughter was in, it was believed and communicated that a student by the age of 14 - 16 should be so self-engaged in their education, that they have chosen challenging fields of interest to immerse themselves in, and are studying deeply 10+ hours a day. They are becoming scholars. They are reading the great books, interacting with challenging the brightest minds of their culture.
Do we believe in rigor and passion in our own educations? It's a hard message, but if our free time is filled with unchallenging and mindless entertainment, and if when we talk about our school days we speak of something that is behind us that "we got through," then our children will not know any better. When our major method for accomplishing something is enforcement (which is really what the culture of school is now), we give the implicit message that it is not something that is going to be enjoyed, no matter how much we say otherwise. Want to help your child become a better learner? Let them see you studying math or reading a classic...
All of the best stories of education come from instances where the students became so engaged and passionate that they sought rigor themselves.