Nik,

Daily dose for the omega-3s that you are aiming for is at least 1000 mg/day.

The milk sensitivity could be an issue not only because of the change in omega-3, but because if she still has some sensitivity to milk, it could cause a bit of "brain fog". I believe that you can get organic milk fortified with DHA, so that could be part of an experiment to see if the difference is due to the change in omega 3 levels, or to sensitivity to the milk itself. If she is better on the soy milk, but no better on the fortified cows' milk, then the milk allergy is likely contributing and she should probably stop it, at least on school days. Balancing growth demands against mild allergy/intolerance issues is a tough line to tread.