trying to focus on the pros (and I'm not suggesting that I agree with all these) :
mobility - providing there's a good wi-fi they can be used anywhere around school for indoor and outdoor learning
mobility - teacher with an iPad can move around the classroom better rather than being tied to the PC/IWB at front
cost - less need for dedicated
ICT suites
speed - students can be doing great things very, very quickly without lots of teacher drone
cost - replace IWBs and projectors with cheaper HD TVs; use NearPod to share screens. Ditto with voting system; replace with iPad app.
cost - lots of good apps that are cheaper and better than PC/Windows applications
trust - does your school trust staff and students? Yes, iPads; no, PCs.
SEN - good tool for students with special needs.
pedagogy - if your school ethos is about command and control/petrol pump attendant style of teaching, go with the familiar PCs; if your school ethos is guided discovery, Q&A, feedback, inclusive teaching, creative thinking, go iPads.
pedagogy - students are more excited about using an iPad than they are about a laptop/PC
pedagogy - iPads can be a tool embedded in all subjects rather than having timetabled
ICT lessons each week.
cost - my experiece with iPads is that there is less printing leading to less need for paper stocks, toner and printers.
mobility - options for taking iPads home; extended learning.
personalisation - ebooks, videos and other resources that the individual student needs can be loaded onto their iPad
marketing - are parents going to be more impressed with an iPad school or a laptop/PC school?
speed - very quick to display good quality student work on a digital signage system
decision making - does the school determine what
ICT needs to deliver to support staff/students or does
ICT limit the school to what it considers feasible technology?
resources - staff and students can create and share learning resources very quickly