1. Add a raised and textured surface to information the kids need to learn. To help with reading, for example, write the letters and words on a sheet of paper with glue (glue from a squeeze bottle is easiest), and then shake ordinary table salt over the page. You can also do this with numbers, maps, diagrams, charts, "diagrammed sentences" from English class, and so on. Make the kids' books (their own books, obviously, not schoolbooks or library books) more useful to them with the same technique -- add lines of white glue sprinkled with salt to the illustrations in the books so there's something there to feel. Let the kids do that themselves if they're old enough.
2. To help with math, give the kids lots of things that have interesting textures, to be used in counting and the basic operations -- adding, subtracting, multiplying and dividing, fractions. You don't need the fancy expensive sets of math doodads sold by the education companies. It's better to have lots of pieces of twigs with the bark still on, rocks with interesting surfaces (we're blessed at our place with rocks from the riverbank that have lots of fossils embedded in them, which would be wonderful for TD kids), big textured buttons, strips of different kinds of cloth .... things you can feel. Resist the temptation to make the kids put all these things together in matching sets; if they want to do that, that's fine, but if they'd rather add three buttons and a rock to two twigs and a strip of silk to get seven, that's fine too. Cheap calculators with big buttons are good. An abacus is good.
3. Give the children scissors and glue and your non-obscene junk mail and show them how to make collages. Show them how to add texture to illustrations in their books by cutting out pieces of cloth and textured papers and similar materials and gluing them on the pages -- like cutting out velvet wings and gluing them to the flat paper wings in the picture of the dragon.
4. Writing, fortunately, is a task that's done with the hands; that helps. But you need to keep firmly in mind the fact that how the writing looks is not the point and will not matter at all to TD children. Big sloppy crooked writing, tiny pinched crooked writing, smeary smudged crooked writing, writing that doesn't stay on the line .... resist the temptation to criticize these things. The goal is that writing should be a pleasure for the child. Children who think of writing as a pleasure can be gradually led in the direction of a tidier product with Correct Spelling And Punctuation, over time. Children who think of writing only as something that's sure to get them in trouble will restrict themselves rigorously to very short sentences composed of words that they are absolutely positive they can spell.
5. Teach the kids to type, obviously. Typing is handwork and handplay.
6. Teach the kids fingerspelling and some sign language. There are all kinds of books and videos teaching Sign available now; a Google search will find you free online Sign materials. Learn the material yourself, so that you can join the kids when they're using it.
7. For subjects like social studies and history and civics, do what you can to "translate" the information into touch form. Encourage the kids to make models of forts and castles and bridges, encourage them to act out historical events and elections and court cases, encourage them to put together inexpensive collections that are relevant to the subjects. Find the paragraphs of text that absolutely have to be learned for the tests and turn them into paragraphs of touch language for the kids, or help the kids do that themselves if they're old enough. Discuss them with the kids in touch language. Talk with the kids about whether they think that the touch version's words and phrases mean anything different from the sight or sound words and phrases in the original.
8. Help the kids put together a collection of figurines and sculptures and carvings -- a collection of "handleables." If you're in a financial position to buy "good" pieces, that's wonderful. But how the items look is irrelevant; what matters is how they feel. And the kind of tasteless kitschy trinkets you can pick up at yard sales often are perfect for handling -- plus having the advantage of not representing any kind of financial loss if they get broken.
9. Talk touch language with the kids whenever you can; when you can't, try to use language that's sensory-system neutral.
10. Finally, there's the obvious: Provide the kids with as many hands-on things to do as you possibly can. Weaving. Needlework. Modeling clay. Board games that have actual pieces to handle and fool with. Gardening, in real dirt. Woodcarving. Carpentry. Sports. Dancing. Puttering. Working on the car. Dressing up. Playing in water. All that good stuff. Keeping in mind at all times that it doesn't matter how it looks, or how it sounds. All of the rest of the child's world will provide an abundance of emphasis on how everything looks and sounds; you don't have to worry about any lack of that sort of information.