I have a golden retriever 15 weeks old. She is alright with the family. However, when she meets strangers/ other dogs, she will get over excited and out of my control. An example is when we went to the preschool, she just never stopped pulling the lead and rushed to other dogs and people. Never gave up, ever. This made the class futile and awkward for me. Actually, she learned sit, down, come, up well. However, just without distraction. However can I do with this problem?