I currently have 1 child HSed and 2 in school. Actualy, at the present moment, 1 child still asleep in bed and 2 in school.
All 3 were in school up until a year ago (I pulled DD2 out in the middle of last school year; we started in January.)
DS is a loud and boisterous child. In other words, he's a normal, healthy, bright 6yo. But I'm not a "normal healthy" 35yo- I'm dealing with a chronic illness that saps my energy, and I'm super sensitive to noise and easily overstimulated. A day that's "good" for me would be "boring" for him. A day that's "fun" for him would be "overstimulating" for me.
I simply cannot keep up with him or provide him with the kind of stimulation he needs. I first put him in preschool at "almost 3" because he was watching way too much TV when I lacked the energy to even take him outside to play. I was hoping I'd be able to handle him better now that he's bigger, so I didn't put him in camp this summer. It was a disaster. He was bored and acted up because of boredom.
Academically, I'm not too happy with the pressure and the way things are being taught in the school environment, but his needs for social interaction, physical activity, etc are simply too much for me to handle and his overall needs are much better met by having him in school.
My 13yo is a very social creature and is horrified at the thought of only seeing her friends 2-3X a week, rather than daily. She also craves academic structure- I'm sure that COULD be provided at home, but for her the "schooly way of teaching" is a perfect fit for her learning style- severely limiting the benefits of HSing for this particular child. Maybe she'd look at things differently if she'd been HSed since kindergarten, both in terms of academics and socially, but that's not how things worked out. Even if she had been HSed since kindy, it's still possible that I would have put her in school by now.
My middle child was NOT doing well in school. She didn't do well in public school and she didn't do well in private school. She has a unique learning style and it's hard for her to learn in a classroom environment. She's a lot like me: easily overstimulated, needing a lot of downtime, and very self-directed. If she wants to learn something, she'll focus on it and get into it deeply. But if she doesnt' want to learn something (ie, it's taking her away from something else that she's focused on right now) she simply can't focus or absorb anything that's being taught.
So it's easy for me to facilitate her learning at home- as long as her siblings aren't around to distract her. We both have similar needs for quiet. She does beautifully with 2-3 activities per week- it's enough to keep her from being bored and to allow her to make friends, but it doesn't overwhelm her and it's within my physical limits to take her to these activities. Some weeks there's only 1 activity, other weeks we've had up to 4, but it's still far less draining than being in school 5 days a week.
We're taking things year by year. For next year, I plan to do the same as we did this year: DD2 home with me, and DD1 and DS in school. I may keep DD2 home all through high school; but for now I've only made a decision about 7th grade. I'm positive I'll keep DD1 in school through high school graduation. I'll probably do the same with DS, but I may consider HSing him in the future- my health could improve, and he may be less of a handful as he matures.
There's no reason you can't do the same: each year evaluate the options, look at your kids' current personalities and learning styles, what each local school can offer them, what you can provide outside of school (including HS activities and what the local HSers are like) and decide what's best for that particular child at that particular time.