Homeschooling hits record numbers

Of these, most are easily handled. I am in a midsized city and there are plenty of groups that offer music, robotics & engineering, speech & drama, etc. focused towards homeschooled students. That, plus the rise in homeschool "pods"/co-ops means socialization and activities are very available to students & parents who want them.

Sports might be the challenge. Many US states have athletic associations that handle most K-12 sports, and they require enrollment in an accredited member school. I am aware of several homeschool specific athletic associations in my area, but all are targeted towards religious homeschoolers. Not certain what secular alternatives would exist, but soccer is very popular & there are plenty of competitive academies that operate outside the school ecosystem.

Besides big ones like soccer that you mention, more niche sports are often partially or totally outside of school systems.

Fencing for example, is usually clustered around external clubs. Very few high schools will have fencing teams, and in a lot of cities even the high schools that do have fencing teams will be kind of a joke compared to the club teams.

I know several homeschooled students who played varsity sports for their local high school (the one that they would have been attending). I'm not sure about the universality of that, but that's an option for at least some people.

This comment made me curious so I did some research. Of the sports offered by my local school district (in the top 30 for enrollment in the country), I can find an alternative for homeschoolers that offer competitive opportunities for every sport but bowling and football.

Of the others, there are either homeschool alternatives that are explicitly secular or at least not overtly religious, or there are competitive clubs. All the schools have track & field, but there is a large homeschool league. And the district has a few schools with pools and a few more with swim teams that practice at the city pools, but the local swim club is the one turning out the Olympians – but even then, it also seems to have plenty of offerings for kids who won't set a world butterfly record. Football, I imagine, is just so popular that the private/public schools take all the players.

I think it's patchwork & has changed over time. When I was at high school one of my friends who was homeschooled competed with me on our academic team. His older (and far more athletically gifted brother ;-)) lettered in several varsity sports. But now that state's athletic association explicitly says no to homeschool students.