I have a four year old grand-daughter who took a shine to computers three years ago and some. She used to watch me fix them, and when she was old enough that she could walk, she would hold a flashlight for me such that I could see what I was doing inside a desktop case.
She graduated from flashlight duty to playing the three games in Windows 7 ‘Purble Place’, and it was quite something to see her work the mouse ‘two-handed’. I was amazed that she could control it as well as she did.
Anyway, I connected a laptop mouse up because my mouse was a little too large for small hands, and she took another quantum leap in mouse control. It then occurred to me that maybe a trackball device would be better for her. As it happens, I have a local client who just happened to have a Logitech Trackball but wasn’t using it. I asked if I could borrow it for a while such that I could assess its performance in small hands.
My grand-daughter spends more time on her computer now that it has a trackball, and requires less general help than before. She cups her right hand around the front leading edge of the ball, and can place the pointer very quickly on any part of the screen, and the weight of clicking the left button no longer pushes the pointer out of position.
So, if any of you have a ‘little one’ who shows a penchant for using a computer, consider getting a trackball. The photo shows the Logitech T-CM14 Trackball. It is a PS/2 connection and has only two buttons. Later versions are no longer the ivory colour, and have four buttons which could cause confusion, but the older type can be found on eBay.