Home school co-ops are the answer, as are non-academically-oriented groups, such as churches, as well as sports and/or music. I was home schooled from 2nd grade through high school, and I was involved in all those things.
The old trope of all home schooled kids being antisocial shut-ins needs to die.
The old trope of all home schooled kids being antisocial shut-ins needs to die.