First, i think it's so important to understand that learning looks so different in each child. There's no reason to panic if a child appears to be 'behind' or frustrated by a certain school subject.
Secondly, the number one motivational tool that a mom has at her disposal is *herself*. Children want one on one time with their parents - taking the time to give that child individual attention will do wonders for their education - & for your relationship too. Plod through - question by question - with your child - take interest, time and have the patience to take each tiny victory. It'll come...