An excerpt from Adapting Creatively by Rose-Marie, July, 2012.
...Introduce screens with the end result in mind.
How many buttons on a page will a child be able to access in the future? No one has a crystal ball, so you’re just going to have to make an educated guess based on your child.... The more buttons per screen, the fewer hits are needed, whether you are accessing words through categories or semantic compaction.
Take the screen that is your end goal and hide all buttons except the [number of] starter words/categories your child is using. He still has access to the same eight selections as the large keys filling the screen. Yes, these buttons will be smaller, but they are surrounded by plenty of null space that won’t activate if he hits it. You might be surprised how fast he can learn to target the smaller button size.
When it is time to add vocabulary, you UN-hide hidden words or categories. They won’t change anything your child has committed to motor memory; they simply begin to fill in void space.
Remember learning to touch type in your keyboarding class? You started with the home row of keys: asdf jkl;. It wasn’t much; you were limited to words like “fad,” “ask” and “lass.” But after a few days (weeks?), the teacher introduced “e” and “i,” and that opened up a huge new world of words! Now you had command of “alike” and “fleas” and “skidaddle!” The good news is that you didn’t have to relearn where the home row keys were located; they stayed consistent while new keys were added. Eventually, you mastered all 26 letters of the alphabet, along with some punctuation and formatting keys. That’s at least 40 keys...more for the kids who mastered the number row and got an A in typing.
This same concept is what I am asking you to try...