Granted, the information may now be somewhat outdated since the tech sector changes so rapidly. However, this infographic effectively illustrates the shift in our communications from snail mail to email, just by sheer numbers.
In this simple yet poignant video, real people discuss their different relationships with handwritten letters vs. emails. Powerful! This impetus for the creation of this video was a project called "Snail Mail my Email," but whether or not you buy into that, the bulk of the video will likely resonate.
While it's difficult for secondary teachers to communicate with parents weekly or bi-weekly (as this elementary teacher suggests), the post provides a great idea that could be adapted for use by secondary teachers.
Although it is specifically aimed at snail mail in the context of building a business, this article about how to regain the power of pen and ink can easily be applied to the classroom setting. And if writing notes increase buy-in for a business, can't it increase parent and student buy-in of your educational goals and objectives as well?