Today I will Fly! is the first book in the Elephant & Piggie series by Mo Williams. While it is a children's picture book, it is nonetheless amusing for adults and children alike. It is not special among the books in the series; this is not an ordered series, and being first is not relevant to anything. I am noding a brief review (with massive spoilers, but I think that that is okay) as a general indicator of what the series is like.
Piggie runs in and announces "Today I will Fly!" Gerald (the elephant) tells her "no." He then goes on to explain in some detail that she cannot fly, today, tomorrow, or ever, because pigs cannot fly. Gerald is not usually such a wet blanket, but apparently this is a sore point with him. Piggie, undaunted, says that she will try anyway.
Piggie tries running and flapping her wings. She tries jumping. She tries jumping really high. At each step she fails, and Gerald, tiered of explaining her foolishness to her, leaves for lunch. A duck enters stage right, and observes "you need help." Piggie agrees, so the duck helps her.
Gerald reappears to find his friend flying. He is first amazed, and then ecstatic. Piggie smugly informs him that she is not flying -- she is getting help. The view zooms out to show the duck suspending her on a rope around her waist.
Later, as they are sitting together, Gerald announces that tomorrow, he will fly! Piggie is skeptical, but wishes him luck.
But imagine it with cute, expressive, and humorous illustrations (also done by Mo Williams).
As you can see, it is simple, straight-forward, amusing (much more so when you see the character's expressions, though), but slightly longer and with more back-and-forth than your average picture book. This is a fairly standard plot for Elephant & Piggie, although Gerald is not always the bad guy, the plot is not always as silly as trying to fly (although sometime it is sillier), and the story is generally more likely to turn on a squirrel than a duck.
The general consensus among people who read children's picture books is that this is a fun read for all involved, and well worth looking at if you are in the market for read-aloud picture books. I certainly recommend it.