How about a bull terrier or a Shihtzu? for my 13 & 9 YO kids? ?

Bull terriers are pretty destructive dogs. I would go with a shih tzu (I have a bunch of them myself!)

Get a male, and nueter him as soon as possible. Socialize, him, taking him places, and letting him meet people (this is best done on the ground! These dogs are smart, and will consider you carrying them everywhere, as a sign that they need to be protected from the world, and it my induce shyness)
If you get a puppy, make sure the parents (or at least the dam) is really sweet and friendly, and make sure the dog you pick, is one that is already sweet and friendly. BELEIVE me when I say do not go for one that seems shy, unless you don't mind having a pet that only likes you and your family, and not anyone else.
The other option is to find a shih tzu or shih tzu mix in the shelter -you'll already have an idea of what temperament you'll be getting, and you'll be able to pick the happiest, friendliest, most playful dog for your kids.

Other breeds I would consider in your situation would be a cairn terrier (wizard of oz… Toto) or a beagle.
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Spaniel, have loads of energy, are very friendly and love fuss.
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Bull terrier is a great playmate for older children while shih tzu is a great companion for children. You can check out the ff links for more info about the 2 dogs in their relationship with children:

http://dogtime.com/dog-breeds/bull-terrier/children-and-other-pets
http://dogtime.com/dog-breeds/shih-tzu/children-and-other-pets

You also have lots of options, try checking out this link for dog breeds compatible with kids: http://dogtime.com/dog-breeds/characteristic/compatible-with-kids
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http://www.dogtime.com

I think Shih Tzu would be better for you. They are sooo cute too
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Most dogs are destructive if not trained properly or given enough stimulation — Either dog would be fine but the Bull Terrier is bigger and hardier for kids that age.
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a bull terrier is not for the novice terrier dog owner. they are head strong and strong tough dogs, but that is also what makes them great for kids who can be tough on dogs at times. BT's can take anything that is thrown at them (literally). they are clowns and great fun and frustrating at the same time. Shih tsu's are sweet lap dogs and if your kids aren't hard on dogs than one would be fine. Both need training and make sure to get the dog (esp. important for a bull terrier, they are prone to obsessive compulsive behaviors like spinning) from Legit breeders. You can find one via their respective national breed clubs or from a rescue where the foster homes can tell you all about their particular dogs behavior issues (if any)… good luck
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I haven't had any problems with my bull terrier.
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