mean

[leigh2010]

i have tryed everything and he is so mean,he is always
snapping at my grandkids and he is always chaseing
and fighting other dogs what can i do to get him to stop.
or i am giving him away i can't take it no more I LOVE MY DOG but
something has to give HELP ME...................

[Thomas Dock, CVJ, Vet. Technician]

To add to Dr. Hetts' excellent answer...has he been neutered yet?

You definitely need some guidance that goes beyond what we can do in this virtual setting...I looked in your general area and didn't see a veterinary behaviorist or a certified applied animal behaviorist, but I would imagine that your veterinarian might know of someone who can help you.

Don't wait on this...you definitely don't want one of your grandkids getting seriously injured...

[Suzanne Hetts, PhD]

When you say you've tried everything - what have you tried?  Usualy when people say this ths problem is they haven't tried the RIGHT thing  - meaning that whatever techniques you've chosed are not relevant to the problem.
It sounds like you need a professional trainer and/or certified behaviorist to help you.
Is your dog neutered?  has he been to any basic training classes?
You are going to need more help than what is available here in this forum - you need someone to come to you home and work with you and your dog using positive reinforcement based techniques  NOT so called "dominance" procedures