April 12, 1954:
This is the first strip of a new running gag, where Charlie Brown reads something about Beethoven aloud to Schroeder from a book, and he reacts loudly to it. Like Snoopy vs. the Yard or Linus' surreal block-building skills, or indeed Charlie Brown drawing cartoons, this goes on for a bit. Schulz must have found the idea interesting.
April 13, 1954:
More development of Charlie Brown's defeatist personality. There is no hard dividing line between what I call "early" Peanuts and "classic" Peanuts, the strip's evolution isn't actually reducible to those terms, but if we accept them anyway I'd call this definitely a "classic" strip.
April 14, 1954:
This is the first time Snoopy has been shown digging. It's a good pose for him. The first panel shows Schulz's new, loosened style for drawing him. Snoopy has already evolved quite far from the cute little puppy that walked beneath Patty's window.
The throwing of the golf clubs is slightly shocking, because they are presumably the result of an action performed by (gasp!) adults. We should be coming up soon on that weird section soon with Lucy in the golf tournament, which actually has adult figures in it, although never their faces in detail.
April 15, 1954:
Next on his reading list: "Who's On First," by B. Abbot and L. Costello.
April 16, 1954:
This shows, a bit, how Peanuts kids differ from real kids. What child in the world has ever said "Well! What an insult!" in response to anything? I assume from this that the fussing in question is a kind of unspoken, whiny kind of thing, which Schulz didn't attempt to depict visually like he did with the white noise from a few days ago. He could have depicted the singing with a musical note, but it would have spoiled the joke.
April 17, 1954:
Oh I am so not making a "two girls one dish" joke. I'm only mentioning it here to prevent any of you from bringing it up in comments.