Giant Schnauzers are highly intelligent, but they have a bit of a stubborn streak which many experts believe is because these dogs are so smart. With this said, in the right hands and with the correct amount of training, a Giant Schnauzer usually excels at things they are taught to do. If there is one thing these large dogs like, it's learning new things and enjoy taking part in canine activities like agility and obedience, but they need to know who is boss.