I agree with everyone else so far! If you're able to handle HS both at the same time, then go for it especially if pressure from their friends will make it increasingly difficult the longer you wait. Or take one of them out first and spend some time establishing a routine before pulling out the other.
When my oldest started HSing for the first time this past Aug for 6th grade, the first few weeks were really difficult. My DS received pressure from friends at school and so he argued with me the first few weeks over placing him back in PS.(He's a lot better now) I knew I couldn't start HSing my DS10 and DS 11 at the same time since I am still a newbie. I would've went nuts! So I am hoping my DS 11 will be down in a HS routine so that by next year I can focus on my DS 10 when he starts HS for 6th grade since he will require a lot of my attention. By the way I also have a DS5 who I HS, so between him and his older brother, my brain is fried at the end of the day. I just wouldn't want you to suffer burn out. If you're heart has been in HS for a while now, then you are probably better equipped than I am to have both home at the same time.:thumbup: