Experimenting with ergonomic adjustments using Meccano
If you or your child has a spare Meccano kit lying around, don't throw it away. It can come in useful when you are playing with ergonomic adjustments to your workspace. In about an hour, I threw together this little "ramp" to incline my trackball from 0° to a more natural angle.
If you want a wrist support, try stacking a couple of cassette-tape holders.