At my oldest's school all the students have laptop computers, but they also still use books and papers for writing. The laptops are used for a variety of things, and even their textbooks can be found on-line. The teachers teach the students how to take lecture notes on the computers, write reports, make videos, create things, etc. They have an entire technology class they even attend.
Some of you have mentioned electricity... and I think it is always a valid concern. We conserve electricity a lot around here and also use a lot of renewable resources. One thing that I am quite fond of is wind turbines that use wind energy to create electricity. Another thing people can consider is solar energy.
Someone else mentioned teachers being unable to monitor the computers and students checking e-mail. In my child's school it is not possible. Their laptops are monitored from the school. Most websites are blocked, except for pre-approved ones from the school, and if something slips through that is not approved a "red flag" goes up in the principal's office and all the students information is available for the principal to see. Absolutely nothing is secret on those laptops. If a student takes their laptop home and browses unapproved websites, then the minute the student brings it back to the school it will trigger the "red flag" alert. There are still ways the students could "play" on their computers without going on-line, but to get around that issue, many teachers position their desk at the back of the room. That way they can see every computer as they sit at their desk. While lecturing, a teacher can always walk around the room as well. The class sizes in this school are relatively small compared to most schools. The students are expected to be responsible for their own laptops, and can even get in trouble if they do not have it charged for class or they forget it at home, because it is the same as not being prepared for class.
I think the computers are a very good thing, but the school is also not completely paperless. I am not sure how any form of education could be completely paperless. People do need to learn how to write.