Yes, students should use iPads in class, because they are a useful learning tool. There are many things that iPads can do, such as applications that are education that students can use. Students like technology, and will be more willing to participate in learning if they can use technology that they think is fun.
iPads are common today, and teaching children how to use them can be helpful outside of the classroom and possibly at work in the future. They also provide an exciting and high tech learning experience that students may enjoy. They can reduce the amount of paper and pencils used as well which would help students that may struggle to afford supplies.
If the ownership of iPads is on the students, not only it is a affordability issue to the parents, students are likely to be distracted and doing something else like playing games in class. School will need to invest in IT support and maintenance if the devices belong to the school. Moreover, fun and knowledge retention cannot be proved that it is of equivalence.