It’s the ability to learn tools, not the tools themselves, says Mark Shuttleworth. I agree.
I instantly thought of the twins' alternative informal school. They don't use textbooks to teach lessons. Instead, the teachers develop "themes", and wrap all aspects of the curriculum into a project around that theme for several weeks.
For example, one time the theme was "camping". The kids learned about fractions by dividing s'mores evenly (as possible) amongst their camper classmates. They learned some astronomy. They learned some storytelling. They learned how to read maps, and reinforced their sense of direction. Another time the theme was "restaurants", and the final objective was to develop and create a restaurant for their parents. They learned more math by measuring ingredients; they learned about the division of labor, and the importance of responsibility and accountability. They learned reading skills by following recipes, etc.
The kids in traditional schools are often "taught the test", whereby the teachers focus their classes on those lessons that are absolutely essential for passing the mandatory proficiency tests. It is my impression that the kids in these schools are not taught the necessary tools or processes to facilitate life-long learning. Rather, they're taught to memorize those bits most important to pass a specific test at a specific time. Without textbooks, my kids are shielded in some ways from this trap: they'd recognize immediately what was going on if the teachers brought in texts and workbooks and began drilling specific information.
Instead, I believe my kids are better equipped to take the proficiency tests now, without quite as much of the stress surrounding these things as is present at traditional schools, and continue to learn throughout their lives.