fearful, yet aggressive small dog

[Vita]

Bodhi is shy with people and a little aggressive (acting) with dogs. She's half Shih Tzu and half Chihuahua, but from what I've read, she's very Chihuahua in nature. So the new-ish behavior - she turned 1 in June - is not just barking at new people/passersby, but actually running at them barking. Her tail is all the way between her legs while she's doing it, and she jumped up on our yard guy's leg a bit, though she didn't touch him with her teeth/mouth. She just did it again to my neighbor's six-year old grandchild, and the child was a little scared, which seemed to make Bodh a little more aggressive. I dealt with her quickly, and held the scruff of her neck (since she's snapped at me when she's in that mood a time or two, so I don't give her a chance to do that again). But bottom line is, I am disturbed by this behavior and it needs to stop. I know positive reinforcement is optimal, but I don't care WHY she doesn't growl and menace kids - she just needs not to do it. Any experience with this type of issue out there? Thanks!!

[adunphy]

First you need to keep her on leash. The more she practices bad behavior the faster it becomes a habit. Second, you need to teach her basic obedience - things like sit, stay, come, and touch are all useful commands in these instances. finally, find a trainer who can advise you on proper training and care for this dog.

Best.
Amy