Singer Lady Gaga surprised a classroom of youngsters when she introduced herself as a substitute teacher for a new ad campaign. In a video, the 31-year-old can be seen showing up for school in a bright blue suit, reports a website. ‘I am Lady Gaga and I will be your substitute teacher,’ Gaga tells students. ‘Wait — are you the real Lady Gaga?’ asks one student. Gaga has teamed up with Staples for Students for the commercial, to promote successful learning in classrooms. ‘I want kids to love themselves fearlessly. Not having materials at school is a real problem, that puts a child at a deficit. Before we fix that problem, we need to acknowledge that problem,’ she said. (IANS)