Why is Milo so bored before he goes to the Lands Beyond?

Though he does not even know it, Milo's boredom comes from a number of failings in his education about life. He only becomes aware of these gaps when he learns the solutions from people he meets in the Lands Beyond. When he meets Tock, for example, he learns that he has been frittering his time away instead of trying to make the most of it. This makes him feel bored. When he meets Alec Bings, Milo realizes that he has not been enjoying all of the different perspectives available to him. Again, this makes him bored with his seemingly one-dimensional life. All of particular things that make Milo so bored relate back to his education—or lack thereof.

What is the meaning of Faintly Macabre's story?

On the surface, the Which's tale seems like a straightforward history of the Lands Beyond. However, there is much more to her account. In fact it is largely an allegory: a story that mimics a real one by changing some basics, such as character names and settings. Faintly's story is really about the problems with education present in Juster's real world, namely that the different disciplines, number and letters, have become so busy fighting over which is more important that they've forgotten about the big picture. The basic wisdom of common sense, represented by Rhyme and Reason, has been lost because of this foolish conflict, and nonsense has begun to run amok. It is up to young student like Milo, as Faintly suggests, to bridge this gap and restore wisdom to the land.

Why does the Humbug come along on Milo's journey?

The most obvious reason is because King Azaz tells him to. The Humbug, who is a horrible suck-up, has been dancing around the argument over the princesses and trying to take both sides. So when Azaz decides to send Milo on the quest, he is under the erroneous impression that the Humbug has volunteered for the job. Still, this leaves the question of why Juster would chose to have such an obviously unlikable character tag along with his heroes, Milo and Tock. The most likely answer lies in the relationship between Tock and the Humbug; the two characters are basically opposites. In creating these opposing forces, Juster creates a more realistic educational environment for Milo. As much as he is learning from Tock (and the other teacher-characters in the Lands Beyond) the Humbug is always there trying to hold him back or to convince him that it is more important to seem like one is smart than to actually be smart.

Why does Milo fail at conducting Chroma's orchestra?

Milo assumes that the musicians in the orchestra will simply know what to do since, according to Chroma himself, they have been at their jobs since the dawn of time. It does seem strange that they do not know better than to make the sky turn red or plants turn orange. Chroma, the conductor, represents order and discipline without which nonsense would reign supreme. He provides an underlying structure and discipline that, though not immediately apparent, is crucial to the orchestra's functioning. Milo, being uneducated in the ways of conducting and lacking discipline himself, is unable to provide this for the orchestra, and, thus, everything falls apart when he tries to play conductor.