If you're a parent of small children you know all too well how happy they are to drop food while sitting in a high chair. If you're lucky it will drop in front of them and land on the tray, but it seems like a lot of food is dropped on the left and right sides. To help prevent this install high chair "wings" by modifying placemats to fit the sides of your high chair.
Ikea modification weblog Ikea Hackers recommends using LJUDA placemats for this purpose — they're cheap ($US1.49 each), colourful and solid enough that they won't flop around. All you need to do to modify these or other placemats into high chair wings is to cut slits in the placemats so the high chair straps can fit through. Just place the wings under the high chair and feed the straps through the slits. If necessary you can also place a cardboard cutout under the mats for rigidity.
The resulting modification should help minimise both food waste and the frequency you have to clean the floor area around the high chair. The "wings" are highly portable and when attached your kid can pretend they're flying around on the high chair. Win-win.
Highchair "wings" from LJUDA placemats [Ikea Hackers]