I orginally read these strips as part of a larger collection. I can't remember which collection specifically, but it was fun to come back to some old favorites in a new format.
By this point in the series Watterson was almost exclusively working with longer storylines. Of course there were still a lot of single strip gags, but the stories were getting longer and more frequent.
The titual story in this case was the episode where Calvin duplicates himself and proceeds to get in trouble as his duplicates all go and do their own thing.
As an adult I can't help but wonder what stories like this look like outside of Calvin's imagination. Seems to me that a lot of the adventures he gets up to would have to be explained by a lot of running around.
There are too many stories to talk about each one individually, but one in particular does stand out. The baseball story stands out as one of the rare instances when people other than the central cast make an appearance. Coach Lockjaw never makes another appearance, and this is easily the first time some of the other kids at Calvin's school get more than one line of dialogue.
I've found this story to be an interesting one specifically because of the existence of other characters in the story. In the past Calvin has explained spending most of his time alone with Hobbes as being because there aren't many kids in his neighborhood. I think the geater reason for this has more to do with Calvin's world being a very self-centric world. Calvin essentially creates his world around him, from his best friend, to his travels in time and space. Those rare moments when reality imposes on Calvin's being stand out because of how normal they are.
Most of the times those instances are marked as a traumatic event. Such as when their home is broken into and Hobbes's nature as an inanimate object comes to the forefront as the big fear is that he could have been stolen. While Calvin still thinks of him as a real person, under the facade is the idea that he is still a thing that could be stolen, almost as if the trauma has forced Calvin to face reality in a way he is not ready to.
His experience with baseball mostly happens without Hobbes's appearance, one of his only appearances being Calvin complaining about how the game is more fun when play with him, a figment of his imagination. While in Calvin's mind he is playing the game with his best friend, in reality he is only playing with himself, and the addition of others only intrudes on that reality, forcing him into an unfamiliar situation.
Ultimately the experience drives Calvin further into his own mind, an event that is capitalized by the introduction of Calvinball, a sport that has no rules, none of the trappings that make social interaction in a team setting such a traumatizing experience for him. As a criticism of organized sports focusing on the competition rather than the fun of the game it is quite effective. Watterson eschews the rules and regulations of sports, instead providing an alternative where fun is the purpose of the game.
More than anything else, that story is a milestone in Calvin and Hobbes history because it represents the first on page appearance of Calvinball, one of the most iconic parts of the series. I've tried to play the game, but even my relatively anti-rule mind always balks at the "there are not rules" part of the game. If there aren't any rules, how are people meant to even know what to play?
The game was so memorable, that Watterson himself has said that he's had people mail him, asking how to play the game. His answer was always as charming as it was frustrating, namely that there are no rules. But that hasn't stopped anyone, and there are actually people that play the game. Shame it never caught on like Quidditch did.
Every collection of Calvin and Hobbes is an essential part of any fan's collection. But as far as reading material for new readers, this one is especially crucial for the reason of Calvinball alone. The game will be developed more in future volumes, but this is the genesis, the moment where everything that Calvin is was distilled into one singular game.
Buy it Here! Scientific Progress Goes 'Boink': A Calvin and Hobbes Collection