Wheeeee FUN :) Of course, I'm biased, as we're an unmedicated adhd house, too.
You're dead in the black about finding "interesting" things that they'll hyperfocus on... but no matter what you do... adhd little kids do tend to be more labor intensive as pure as not being able to just "set them up". Here's what we do / have done with our adhd kiddo that will trigger his hyperfocus. Obviously... these are just what we do in our house:
- Outdoor toys indoors (we pulled the wheels off of the plasma car and replaced them with rollerblade wheels, because they're quieter http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3... and that's been ridden inside and outside for years). Ditto we allow also razoring and skateboarding in the house. We haven't replaced the Pergo with hardwood for this very reason.
- INTERACTIVE computer games. www.starfall.com , iSpy, http://kids.nationalgeographic.com/ , http://kids.discovery.com/ , and many many others. Kiddo started playing Starfall when he was 2.5 and was reading fluently 6 months later, so be careful with that one, as early readers are kind of a pain in the neck. (Reading + No Impulse Control = Danger)
- HELPING. We didn't bother with a play kitchen, because kiddo started to help cook when he was 1ish. Now at nearly 8 he's my "prep cook". By the time he was 3 he was also our windex-star, doing his own laundry (mum of course has to lift up to pour in the soap, and get the clothes OUT of the wash, but he could bring his clothes down and lob them into the machine on his own). I figured on the cleaning aspect, even if only one square foot got done, it was one square foot *I* didn't have to do. For years he washed all of our cabinets every time we cleaned. He quit 2 years ago in favor of the floors, and boy oh boy, do I miss my clean cabinets. We put on music and dance when we clean, so it's fun. They don't do a very good job in the beginning, but it keeps them occupied, and gets them in the habit/pattern of helping. And with adhd habit/pattern is sooooo key.
- Got a dog. (Yes, for the specific purpose of having someone in the house with a chance of keeping up with him).
- Enrolled him in gymnastics.
- Got Netflix Streaming so I wouldn't feel too bad about TV time (It's hard to feel bad about TV time when it's documentaries put on by NOVA, the BBC, H, etc... and your kids are bouncing up and down running off the litany of things they're memorizing from the 40TH play (sigh) of Walking With Dinosaurs, or The Universe, or Magic Schoolbus.
- Sacrificial rolls of toiletpaper and scotch tape. Oh the mess they'll make. Oh the time it will consume as they make it.
- Shaving Cream + Sliding Glass Door (or mirror) = fingerpaint
- Pots and pans = drums, duct taped pringles can with beans in it = shaker. Tylenol & or drummers earplugs = bliss (drummers ear plugs let you hear everything, but cancel out the sharp part of the noise)
- Alternative ways of walking (aka, "Hey kiddo would you ____crawl like a bug, float like a cloud, run like a mastodon, inch like a worm, etc.____ to the living room and get me the _______?"
- Taping art paper to the bottom of the table and doing Sistine Chapel drawings.
- Paper Mache. Baloons + newspaper + papermache paste + painters plastic
- LONG baths for playtime not just bedtime, with me reading a book right there. (as in a grownup book, to myself)