Another unschooler here!
My definition of unschooling closely matches UnschoolnMa's.
I too am a big believer in child-led learning.
And what that means to me is that we provide a very rich environment that is full of opportunities for exploring various interests at our children's own pace.
Unschooling for me, is reinforcing and providing resources for my children's natural interests. No matter what the age.
And in most instances, I am have not been the teacher for my children. I'm more like a facilitator/resource person.
How I encourage the learning of basic skills is by doing many tasks with my children. Learning by doing is one of the best teachers in my opinion. I also encouraged my children to teach me and or someone else a skill that they themselves have learned and would feel comfortable sharing with others(I got to know a lot about my children's skill level in a particular task by watching them teach).
We use books, the internet, field trips and real life situations to learn. We also take classes and learn things in classrooms, but that is not the focus of our learning. Practice and repetition, if necessary for acquiring a skill is encouraged but not if it is proven unnecessary. We feel the same way about college, if it is necessary for the career choice they have made for themselves, then we are supportive of their attendance and will help in any way we can for them to go. If they decide it is not for them, we are supportive of that choice too.
We do not use a curriculums, workbooks or tests to determine how, why and/or what we learn, but we can and do use textbooks, tests & workbooks if the information in them is useful for explaining a particular learning objective.
I believe that learning can happen at any age and that "You can not be Ahead or Behind Yourself" (this is one of my favorite unschooling quotes).
Unschooling for me is having faith in my children to let them take the lead in their learning quest. And to provide for them the opportunity to experience life in real settings with real goals, and have those goals be what ever they decide they are going to be.
I myself take many classes and I am always trying to acquire new skills so my children see me as a good example of a life long learner. And all of my children, when they were younger and now, have taught me many new things/skills. So in my home, daily learning happens for us all.