Lying miserably in his [cupboard], Harry thinks back about his ten miserable years with the [Dursleys], the flash of green light he remembers from his parents' death, and the dreams he's had of being taken away.

Dudley's Birthday Trip to the Zoo
In the reptile house at the zoo, Harry begins talking to a snake. Then, when [Piers] and [Dudley] notice and shove him out of the way, the glass on the cage vanishes and [Dudley] falls in as the snake escapes.
Chapter 3 - "The Letters from No One" - In which Dudley gets his new uniform and a letter arrives for Harry which Uncle Vernon destroys, prompting a veritable deluge of letters over the next few days. Uncle Vernon then attempts to outrun the delivery of the letters and eventually takes his family to an abandoned hut on an island in the ocean.
After his punishment in the [cupboard under the stairs] is over, Harry spends his days avoiding [Dudley]'s gang and thinking about starting secondary school in the fall.
[Dudley] gets his new Smeltings uniform and parades it around the house - with Harry struggling not to laugh.
Strange Letters Arrive for Harry
The morning after [Dudley] gets his new school uniforms, Harry discovers that [Aunt Petunia] is dying some old clothes to make Harry's. Then, when the mail comes, Harry leaves the room to get it - and discovers that a letter has arrived for him.
The [Dursleys] notice Harry reading his letter and take it away - and then proceed to kick him and [Dudley] out of the room, worried about Harry discovering its contents.
[Uncle Vernon] visits Harry in his [cupboard] to let him know that they are moving him to the [smallest bedroom] instead, but refuses to give Harry his letter.
The mail arrives during breakfast, and [Dudley] discovers a second letter for Harry. Harry realizes more will be coming and hatches a plan to get them.
Harry tries to sneak down to the mailbox in the morning but is caught by [Uncle Vernon]. Then, when letters arrive for the third straight day, [Vernon] boards up the mailbox.