I'm going to be honest - it needs a lot of work.
If this is the start of your story, then it needs to hook the reader and make them want to read on. The first sentence especially, is important. However, when I read your story, it doesn't interest me as much as it could. The first sentence doesn't grab me and neither does any other part of it. You need to really try to hint _something_ in the first paragraph that suggests something is about to take a dramatic turn in Brooke's life. At the moment, you're just describing a girl going to school and to but it bluntly, it's a bit boring.
This brings me to another point - Brooke herself. Her characterization is not constant. First, you show her mucking around playfully in her room and laughing at herself. You make her seem quite fun, playful and potentially outgoing. Then her mother asks her a question, which she answers 'quietly', hence making her seem slightly withdrawn. After that, having barely sat down at the table where her mum is trying to have a serious conversation with her, she just stands up and leaves, which to me, makes her seem slightly rude and conceited. There is nothing concrete throughout the rest of the excerpt which suggests what she is like as a person - no mention of what sort of things she likes, no mention of her friends, no mention of what she thinks of her classes/teachers. Right from the beginning in your story, you should be showing the reader things about your character, letting them get to know Brooke and making them like her.
There are also quite a few grammatical problems (which, from your additional details, I'm sure you expected), but as I've already given you enough to work on, I won't address them now.
So, what you need to focus on immediately:
1. Add some foreshadowing. Hint that something bad is going to happen.
2. Characterize Brooke.
I've forgive you if you want to bash me over the head right now - I may have been a bit harsh and I know what it feels like when someone gives you an extremely blunt analysis of your work. But I also know how important it is that you change this things. Don't give up - your writing has a lot of work and with practice I'm sure you can be quite a good writer.
EDIT:
http://creative-writing-course.thecraftywriter.com/writing-characters/ ^That is a site a found on developing characters. I think it would be worth a read. Also, there is a saying I like that I think might help emphasize the point:
"Never let your character eat an apple when he can be eating fried Cheerios."
This just basically means that you should be constantly developing your character. Show Brooke eating something unusual that both makes your writing more interesting and characterizes all at once.
This will also help slow down your writing. Although you said you've made an effort to do this now, it still goes WAY too fast. I mean, she gets up, goes to school and has soccer training all in the space of a few paragraphs. Add in more details, make it interesting and try to stretch it out to at least a chapter :)
Good luck!!