We use a variety of curriculum between the two children.
While there are some very appealing pros to buying bulk curriculum, I found that for our family a mix of curriculum that caters to each child's strengths is what works best for us.
My oldest is in 10th grade. This is also her first year of Dual Enrollment at one of the local Universities. This semester she is enrolled in Psychology, and next semester she will be taking a foreign language and American Government. At home she is using Yay Math for Algebra 2, IEW Elegant Essay and Windows to the World, Fix It Grammar, Spelling You See, Friendly Biology, Bob Jones World Geography and The Omnivore Dilemma for health. She also dances competitively which we use to count towards her PE.
My youngest, a boy, is in sixth grade. For math he is using Horizons (grade 6), Language Arts consists of IEW Intensive B, Fix It Grammar, Spelling You See, Reading Fundamentals (6), Just Write (book 3) and a Phonics book. For Science we are using Sonlight (Human Anatomy). His History is a mixture of My Big Fat Notebook World History and a World History textbook that I found. I am also incorporating many different types of montessori activities in order to reinforce what he is learning. He is currently doing Soccer, which we count as PE.