Boredom and Unschooling
the state of being weary and restless through lack of interest
Wikipedia's boredom page discusses it in terms of Psychology, Philosophy, Causes and effects and Popular culture
The word isn't very old. The word "bore" referring to a tedious person others would prefer to avoid is from the 18th Century (according to the Oxford English Dictionary), and the French thought the English were that way—sulky, and not very interested in life. The English used "tedious," blaming situations and activities for being uninteresting.
"Boredom," as a word, is from the 19th Century.
The easy way around this is to make life interesting for one's individual children. Rather than setting out a life that they either like or don't, and then blaming them if they don't like it, find value and purpose in what they do like, and live there.
From that Wikipedia article, with its citation:
There are three types of boredom, all of which involve problems of engagement of attention. These include times when we are prevented from engaging in some wanted activity, when we are forced to engage in some unwanted activity, or when we are simply unable, for no apparent reason, to maintain engagement in any activity or spectacle. If that list is to be accepted, then unschooling parents can avoid boredom by finding ways to help children engage in wanted activities, not pressing them to engage in unwanted activities, and provide options to any activity or spectacle. (I'm thinking having quiet toys, a book, a Gameboy, smart phone or iPad on hand.)