It's a difficult age. is she over stimulated when she is yelling at strangers (walmart usually does it)? Do you have a routine down? How often do you use positive reinforcement? make a huge deal of all of the good little things. When she acts out, calmly set her in a time out, kneel down in front of her holding both hands to keep her attention and simply say, "blank was not a good choice.think about better choices. next time try blank instead" and walk away. By staying calm and not making a big deal about the behavior you are starving the beast so to speak. Usually the negative attention getting behaviors will switch to positive behaviors. These things do take time. She really is in an age where empathy is only a foreign concept and she is the center of the universe. This age is all about understanding cause and effect in the world. Tots do understand a lot of what is happening around them but the understanding is very limited and self centered. Helping her understand that when she does this behavior it makes mom sad or it can be dangerous will help her form better decision making choices. If you feel her behaviors are related to sensory overloads, make a "calm down" belt to set on her shoulders or lap in environments that usually cause meltdowns. This is essentially a homemade hot pad. Have her pick out an adult tube sock, or pick out a white one she can decorate with cloth markers, stuff it with 2 pounds of rice and maybe dried chamomile and lavender and sew the end shut. If she's fidgety, sew on or hot glue button eyes and different textures here and there :)

My stepson is that way. I would turn the tv off and make is super quiet and face the fridge for two minutes. Because at the time he was 2 1/2.maybe take away her toys for a while ?

we took away cartoons and put them both to bed at 7:30 instead of 8. we have taken away sugary snacks and juices. it has helped a little bit

my almost 4 year old and 5 year old have been acting out. especially my 5 year old. especially when it comes to school