to run away?"  The author doesn't answer that question right away either, which heightens the suspense.  It's not until chapter 3 that Winnie Foster appears again.  In addition to Winnie, chapter 3 introduces the reader to her parents.  Winnie's parents are the reason that Winnie is thinking about running away into the woods.  

Her parents are the quintessential hovering, "helicopter" parents.  They micromanage everything that Winnie does.  

"But, as it is, there's only me. I'm tired of being looked at all the time. I want to be by myself for a change. . . It'd be better if I could be like you, out in the open and making up my own mind. Do you know they've hardly ever let me out of this yard all by myself? I'll never be able to do anything important if I stay in here like this. I expect I'd better run away."

Winnie does not run away right then.  Instead she returns to her house; however, that night she and her grandmother hear a strange musical sound coming from the woods.  By the next morning, Winnie has talked herself out of running away.  

"Where would I go, anyway?" she asked herself. "There's nowhere else I really want to be."

Winnie then becomes angry at herself for not being brave enough to follow through on her decision.  She desperately wants some freedom and independence from her parents, but she can't quite muster the courage to go anywhere.  Then Winnie decides that perhaps she could do a sort of half run away.  

Well, anyway, she could at least slip out, right now, she decided, and go into the wood. To see if she could discover what had really made the music the night before. That would be something, anyway. She did not allow herself to consider the idea that making a difference in the world might require a bolder venture. She merely told herself consolingly, "Of course, while I'm in the wood, if I decide never to come back, well then, that will be that."

What prompted Winnie to venture out into the woods the first time can't be pinned on a single thing.  It's a combination of how she feels about her family, the music she heard, and her attempt to take that first step toward gaining independence from her family.  The woods happened to be close to their house, so they were immediately accessible for Winnie to take her first small steps toward independence.  

Winnie's first foray into the woods is caused by a combination of two things.  The first thing that draws Winnie to the woods is her desire to escape from her parents.  The day before, Winnie was contemplating running away from home.  Her parents are not nasty, but Winnie is sick of their nagging.  

"That's just what I mean. It's like that every minute. If I had a sister or a brother, there'd be someone else for them to watch. But, as it is, there's only me. I'm tired of being looked at all the time. I want to be by myself for a change."

Winnie chickens out though and doesn't run away.  In chapter 4, Winnie and her grandma are outside talking to the man in the yellow suit.  During their conversation, they hear a sort of music coming from the woods.  Winnie thinks it sounds like a music box, and grandma is adamant that it is elves.  

The next morning, Winnie wakes up really early.  She is still contemplating running away, but decides against it.  Winnie is a little bothered by her own cowardice, so she decides to slip out for a little bit into the wood.  She reasons that maybe she can find out what caused the music.

"Well, anyway, she could at least slip out, right now, she decided, and go into the wood. To see if she could discover what had really made the music the night before. That would be something, anyway."  

For Winnie Foster, the woods represent a rare taste of freedom. She is an only child and feels like she is constantly being monitored by her parents. She feels stifled, and she wants nothing more than just to be herself. The woods hint at a world beyond, a world of freedom and opportunity for adventure which she can explore at leisure, far from the prying eyes of her overprotective parents. How she envies the toad and his freedom! Sick of being ordered about by her mother and grandma she makes an important decision: she is going to run off to the woods and escape.

Although still only a child, Winnie does not feel she should be treated like a little kid. However, that is precisely how she is treated at home. That is why the woods look so inviting. There, she can finally be herself, just like the toad can be true to his nature too. There is a portentousness to Winnie's desire to be a grown-up. Over the course of the story, she will be faced with many situations that force her to grow up very quickly indeed. Ironically, for reasons that will become clear as the story unfolds, this will take place in an environment in which the people she meets, for a very strange reason, are unable to grow in the way that she does.