As online classes, we can develop something similar to FaceTiming. Each teacher can create their own virtual class and students are going to watch it on their device. Students can ask questions at the same, they can interact virtually. The length of the class would be the same as the normal class. The teacher would be able to see the students through the camera and the tests can either be assigned to be taken in person or online with the teacher. The cost would be equivalent to the actual online classes, but at the same it allows real class interactions with each other like in a normal classroom.