I have not found any preschool curriculum that my kids learn from better than just following their interests, reading lots of books, and playing outside. I know it sounds trite to say that your kids will learn more just by being kids than you could ever teach them, but at least for my kids, that's been true. I have
contributed to their knowledge by showing them where and how to find out more about what they want to know, and reading to them continually, but I have not really "taught" them anything. The "tangible results" your dh wants to see are the tricks that kids in preschool are taught to make the parents think they are learning. The actual learning, well, at the preschool age it's usually not tangible, but if you observe your kids, you know it's there. If the kids express an interest, I get them books about it, find websites about it, show them a craft about, get a video about it, talk about it, etc. I don't direct their learning, I merely give them options.
Our "preschool curriculum" has consisted of:
*Children's museum
*Usborne internet-linked books that reflect the kids' interests, not what I want them to learn, and include links to websites that offer activities to add to what was read about
*Construction paper, paint, glue, scissors, glitter, crayons, markers, pipe cleaner, pom-pons, etc., available for them to use as they wish. The other day they made planets.
*Library storytime
*Parks
*Gardening
*Cooking
*Riding bikes
*Swingset
*Singing songs
*Spanish class
*A big world map
*Magnadoodles
*Playsilks
*DK "First" books (Atlas, Encyclopedia, Dictionary, Book of Animals) to be consulted as the children desire
*Lots of card games
*Lots of board games
*Lots of legos
*Sitting together on the porch swing/on the deck/in the dandelions in the front yard and talking
*Baths
*Body paint
*Mud
*Friends
*Making beds and putting away laundry
*Listening to world music/kids' music/bluegrass music/old timey music/classical music/punk music/Irish music/popular music/80s music/meditation music
*Going to the Dharma Center
*Watching videos about animals
*Hugging and kissing
*Taking naps
*Lots of bandaids
*Calendars
*Workbooks (Ramona's favorites)
*Starfall.com
*Fridge Phonics
*Jack's Big Music Show
*Taking walks
*Swimming
*Playing in the snow
*Puddle stomping
*Getting bored
*Finding something to do
*Arguing and making up
*Lots of snacks
*Visiting Daddy at work
*Riding the public bus
*Riding the merry-go-round
*Grocery shopping
*Temper tantrums
*Thousands upon thousands of books
*Etc.
Seriously, there is no preschool curriculum that could ever be dreamed up that would benefit your kids or produce more "tangible results" than these things do. IMO, you'd be wasting your money to even try (and this from someone who has wasted money trying)!
Namaste!