Homeschoolers get several added bonuses. As the principal of my school I sit down with the children and together we structure the classes. The only limit to the number of classes my child can take is what I can pay of the tuition. My kids go to a college where we get five hours a semester of tuition free classes and pay less than $50 in fees. This saved me about $5000 this semester alone. All of my kids will graduate with over thirty hours of college credit. The students are taking class either online or at the college right along side everyone else. I know of several parts of the country where the high schools offer dual enrolled classes taught by the regular teacher not the professors and sometimes the quality can be lacking.
Then there’s the added bonus of getting to know the professors and the school better before you actually make the decision of what major to choose. You have up to two years with no declared major, just taking the core courses that are required to graduate. Those relationships you build in the high school years can be leveraged into positions of leaderships in various honor societies or clubs merely by the fact of being around the campus and observing before you are actually able to participate fully in the clubs.
I have heard that parents think that the curriculum may be too hard. Most of the entry-level courses require participation, doing homework and showing up. They are not difficult nor are they meant to be. We ease ours in by first taking art appreciation and then moving on from there. I know from experience that most professors love homeschoolers and are always glad to answer questions.
I just encourage every parent of a homeschooled student to take full advantage of this if possible. It is a rich opportunity.