In language learning, it will be text or audio documents fleshed out outside the school and used in the countries speaking the language. In mathematics, it will be problems students can meet in daily situations or at work.
One argument for an authentic situation is the same as in project based learning: it helps to give the student a meaning about what is taught. The second argument is to confront students with real life situations they will meet in their future adult life[1].
This pedagogical methodology was promoted in the new education trend by John Dewey, Célestin Freinet and Maria Montessory as well.
Nevertheless, using authentic documents or situations does not ensure successful teaching. Appropriate scaffolding[2] is needed to shorten the distance between the domain knowledge of the authentic situation and the learner's cognitive representation of this domain.
Moreover authentic documents may hold too much information not pedagogically meaningful, for learners new on the topic taught. This additional information will be superfluous noise making learning more difficult[3].

Dynabook implications

The Dynabook should be able to both visualize and acquire authentic documents with supplementary analog inputs that will help to acquire arbitrary data from science experiences.
A teacher could use or craft Dynabook's tools to edit the authentic document, with the intent to reduce the complexity if necessary: an audio/video editor to cut and apply slow playback. An image editor to simplify a complex object picture to a schematic one.
From his Dynabook, the teacher could share such documents with his student's Dynabook.
Any opinion on the topic? If so leave a comment for further reflection.

Thanks to Michael Davis for his editing.

Notes

[1] A. Tricot, L'innovation pédagogique, Retz, 2017
[2] https://en.wikipedia.org/wiki/Instructional_scaffolding
[3] D. Robin, Usages et apports de la 3D en maintenance aéronautique (Phd thesis), 2010