I am a senior in high school right now, so I completely understand your frustration with school. You are NOT a loser because you dropped out of high school because you have plans and goals for your future. You know what you want to do, and how you want to get there. I know that if I dropped out of school my parents would be very upset, so I can only help based on that possible reaction. You should probably expect some kind of negative reaction on their part simply because they are concerned for you, your future, etc. This is understandable, but do not let it deter you from sharing your decision with them. You should approach them when they are not under any stress from work, relationships, money, etc. Ask them to listen to you before interrupting. Make sure you are all sitting down, as well. This way people can't get mad and stomp out. Also, its probably a good idea to have INFORMATION about your plans for the future, like which Community College you want to attend, how you plan on getting your GED (which I think is needed to go to community college, maybe not), which classes you want to take, etc. This shows resonsibility on your part. Actions speak louder than words. While it is honorable to have the INTENT to go to school, their reaction to your dropping out will be better if you have a PLAN. Also, you should probably have something to do during the week since you aren't attending school yet. Maybe a job or something. This will also demonstrate responsibility.
I really hope this helps, and I wish you luck!!