Oh, yeah... you'll (probably) have to find someone much younger if you don't want that response. Sorry!
My kids are also very different. My oldest is the calm, academic type, and my youngest is the one getting into trouble when my back is turned.

The same curricula may or may not work for both. It really just depends. For now, you should consider buying/making some "special" things for him to do that he can ONLY do during school time. Let him know they're special, and he can't use them without asking. Maybe some funky kind of crayons, a (sealed, dry) water bottle full of sand and "buried treasure" (paperclips, craft jewels, etc.), and things like that. Google "tot school" or "tot boxes" for lots of great ideas.
For her, you may find that you're jumping and skipping and stopping a lot at first. If you come across something she has clearly mastered, skip it. Don't make school boring. If something needs a little work, don't do everything the curriculum suggests. Just do what's necessary to get her up to speed. If you come to something she clearly has no clue about, take your time with it, and don't get frustrated. There will almost certainly be some things that are way ahead, right on target, and perhaps even a little behind at this age because skills vary SO WIDELY in the 4 year old age group. If someone tells you she can't do something because she's x-years old (no matter the age), ignore them, tell them the kids in China learned it 2 years ago, or tell them she picked it up while watching TV and eating Fruit Loops.

"I tried to stop her, but she grabbed the dictionary and locked herself in the bathroom!" LOL!!
Seriously, though, just get lots of great books with rich vocabulary and thought-provoking pictures, and tie them into whatever you're learning. Ask questions like "how do you think ___ felt when that happened" or "what do you think will happen next" or (for non-fiction) "how do you think that works?" Learn from life, and answer everything you can, even if you have to use google. (I finally just taught my kid to do it himself after a while. LOL!)