Desmos has changed the way they allow CPM teachers use the materials. If they had previously been approved at: https://teacher.desmos.com/cpm , they should still be able to access the materials. Otherwise, they will need to agree to piloting the materials so that Desmos can evaluate the effectiveness of the materials.
Also, the March 2018 newsletter says to go to learn.desmos.com/cpm. That site has been taken down. Instead, teachers should go to the link above!