Well you have a plan it sounds like, and it's a great place to start... that is if it is legal for your age, etc. Remember to factor everything in so that once you do move out, you won't bring yourself down by having additional costs that you didn't think of before. (Such as TV/internet/phone/power/water, etc.) Unexpected costs come up too, so having a good savings is extremely important plus having a steady job. (Sometimes difficult if you are still in school as well.) Living at home can be a horribly awful thing. Sometimes the need and want to get out can blind you to other things going on, so please take everything into consideration. Also, what is your reasoning for needing to get out of your parent's house so badly? That may be something to focus on for the time being. If it is simply that you feel you do not have direction, then having a good job and trying to bring up your grades while you are still at home may be a goal enough to temporarily lift your spirits up. Try getting a hobby or something that you like to do. This could be as simple as taking an evening walk (air is good for you and so is the exercise!), joining a dance class, learning how to make pottery, making bracelets, playing chess, anything that your heart desires really. This will give you something to look forward to through out your day.
Often times grades are a reason for feeling down. I can personally relate there. It didn't really get better for me until I got to college where I could focus more on things that interested me, but while in high school, I kept a level head by having things (music and dance) that really interested me and gave me something to look forward to. Grades are there as a guideline to your progression, so perhaps if you want to try to raise two grades by a certain percent (2, 5, 10.. whatever you set as a goal for yourself) that could be a way to gain a sense of accomplishment as well.
The feelings of wanting to get out are extremely common. I get them all the time. The best thing I have found to help is to actually get out.. not necessarily on some huge trip or moving out of town or anything that extreme. Maybe a weekend camping trip with a couple friends or staying a night in a hotel and going swimming.. just to get out of a regular routine. Even changing up how you organize your day can be enough of a contrast sometimes to make things seem more exciting (even if they actually aren't.)
The things you are feeling right now are fairly common, so don't drag yourself down about them. If you can think of a solution to the problem, but it doesn't sound fun.. keep thinking! There is always more than one way to do things.
Oh, and I love that movie :)
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"If you stand in front of a mirror holiding a dozen roses, you'll see
thirteen of the most beautiful things."
"Don't have regrets because at one point, you were doing exactly what you
wanted to."