These magazines are absolutely free for teachers. Each of these magazines are also available online if you prefer to read them there:

Teaching Tolerance from the Southern Poverty Law Center
Not necessarily related to technology but a fantastic resource for teachers of all levels concerned with promoting environments of fairness and respect.

Tech Learning
has many excellent articles written for teachers of different levels of technology know how.

T.H.E. Journal
written for intemediate to advanced teachers of technology