We are using Ambleside Online for our curriculum and we really do love it. It is an academically challenging and riqorous curriculum and is based on the methodology of Charlotte Mason. This is our second full year of homeschooling and we are using AO again (Year 7) for ds' 7th grade.
One of the great things about AO (http://www.amblesideonline.org) is that it is very flexible and easy to implement. Most of the planning has been done by the Advisory board and yearly schedules have been created so that you can start immediately. You do have to get your books, either from the library, online (e-texts), downloads, or purchase them. But other than that, you can pretty much take the yearly schedule and begin school with one simply MS Word document.
Now, I would be lying if I said that that was all there was to it. I do know some families with older teens who simply print off the yearly 36-week schedule and hand it to their student. The student manages their time and schedules weekly meetings with their parent to go over their work and discuss certain books/topics. For younger students some sort of schedule or system is needed, just to help the student begin to learn how to manage their time.
My goal is to work towards helping my student learn how to manage his time. He struggles with time management so we often have to use the kitchen timer to help him focus and stay on task. I do have a weekly routine set up and we follow it pretty faithfully. Our schedule works well for us and so here it is broken down by the days of the week.