Dog Behaviour Question?

I have a very lovable, nice natured GSD Bi**ch who is very affectionate and playfull. She is very submissive and very friendly. She always picks up one of her teddies or ball and shoves it in our face and when we try and take it from her she turns her head and wont let us. She never growls and her tail is always wagging its as if she's teasing us with it. Can anyone tell me what this behaviour is and do any of your dogs do it???