The Norwegian Ministry of Education and Reasearch released a report recently detailing their deployment of Skolelinux, a thin-client Linux model for schools built on top of LTSP (Linux Terminal Server Project). 234 schools, 33,000 client machines, and 101,000 pupils and teachers. (See http://d.skolelinux.no/ for the Skolelinux site, http://d.skolelinux.no/ressurssparing.html for the report--only in Nowegian.)
South Africa's TuXlabs project has installed over 160 labs in schools there. Chile announced a few months back a plan to install Linux thin client in 600 schools. Brazil has over 140 computer labs for the poorest of the poor in Sao Paulo--also with Linux thin client.
I'm hoping we can mount a comparably visible Linux thin client presence here in the United States. It may start with an impoverished public school district, or a chain of private schools. Or maybe as a second-tier effort to the work being done in Indiana by Mike Huffman as part of their very, very interesting INAccess program (http://www.doe.state.in.us/technology/inaccess.html).
I keep hoping some successful business-person, whose company has really benefitted from Linux or Open Source, will decide to make a bold move and help fun Linux thin-client labs in some large number of schools...