There are many supplements out there you can try you say the Adderral isnt working in some case it can make your child worse, check it out with your prescibing Doctor, Many experts are telling parents now to get their children taking a multiple -vitamin-mineral supplement with B Compex and Vit C ,fish oil has been shown to be useful also.There are also other supplements specifically for children with ADD one is called Attend by Vaxa, Have you found out about his behavior ,are there specific things that set him off into a tantrum,could he be trying to get more attention, has he any jealousy issues towards his sister, sometimes if you can pinpoint and address what upsets him , why does he use his sister as a "punching bag" your words, focus on his positive side . Does his Dad play with him and do sports and outside activities.