One thing that helped me through the phase was when I read how everything at this age is a science experiement. OK, so I throw peas and they roll away, cool lets's try it when I through oatmeal! Nope, oatmeal didn't roll, hmmm, are you sure, let's try it again! Nope, still no roll. Maybe I should check those peas, yep they rolled! Wonder what happens if I throw it at the cieling instead, does it roll, noooope, falls down! etc etc etc.
Does not help with what to do about it though, I know, but it helps with keeping your calm! Babies throwing food is babies doing what they are programmed to do, iyswim! Giving LO lots of time to play these types of things with other materials, opportunties to test out what happens with different things when we throw them (from up high and down low!) and so on. With my DS at that age, I let the meal continue but ignored that he had thrown it and did not replace what he had thrown. when he was done and I got him down I made him help me to clean up. As he got older I changed the approach, but at 13 months I didn't make too much of an issue of it with him.
