Accusative and Dative - Help!!!!!!!!!!!!!!!!

Hi I am really, really confused about the Accusative and Dative cases. I have looked at the grammer section and all the many textbooks I have and I afraid I am still very confused!!! Could anyone help me to understand them in a really, and I mean really simple way as if maybe explaining to children!! I have lots of homework to do using A and D sentences and am really bogged down! Its a huge stumbling block - please help!!! Danke Dale