How does Tom attempt to win Becky’s affection?

In Chapter Seven, after discussing rats, chewing gum, and circuses, Tom asks Becky if she would like to be engaged to him; his definition of engagement is simply telling "a boy you won't ever have anybody but him" and then sealing it with a kiss. After whispering, "I love you" in each other's ears, the bashful Becky and Tom kiss. Inadvertently in his giddiness, Tom blunders that he was previously "engaged" to Amy Lawrence. After learning this, Becky rejects Tom and breaks into tears despite Tom's pleading. Tom attempts to win her over again by giving her his most prized possession ­ brass drawer-knob ­ but she throws it at the ground in anger. Heartbroken and enraged, Tom marches out of the schoolhouse.