SAN FRANCISCO - As San Francisco schools reopen, some students will be physically in class, while their teachers are at home.The San Francisco Chronicle reports close to 500 teachers and aides have received medical exemptions allowing them to teach remotely.A substitute or another staffer will supervise the class.The number of teachers and aides on a medical exemption far surpasses neighboring districts and is expected to cost San Francisco more than $40,000 per day for substitutes to supervise students in those classrooms, or about $1.5 million before summer break, the Chronicle reported.Parents tell the paper they are frustrated by the so-called "Zoom in a Room" approach."It’s beyond logic," parent Kira Gaber, whose kindergarten son.