On Sat, 12 Aug 2006 19:39:35 -0500, Emily
wrote in :

In addition, all CFI's are
required to complete Security Awareness Training.

Perhaps the reason you received the notice is, because there is no
record of your having completed the above required training?

Security Awareness Training

TSA defined “flight school” to include individual flight
instructors because the agency believes that individual flight
instructors are just as likely to experience suspicious
circumstances and activities of individuals applying for flight
training as large flight schools. Under the IFR, individual flight
instructors are required to conduct security awareness training
for any of their employees, including themselves. The IFR provides
the option of using a security awareness training program
developed by TSA, which will be available at no cost to flight
schools by contacting TSA (703-542-1222 or ) or
by visiting the TSA General Aviation website at
http://www.tsa.gov/public/display?theme=180

You can pose your question to AOPA:

Links:
http://www.aopa.org/whatsnew/newsite...041020tsa.html
http://www.befa.org/pub/tsa_cfr49_pa...r-20041019.pdf
http://www.aopa.org/whatsnew/newsite...tsa_notice.pdf
http://ecfr.gpoaccess.gov/cgi/t/text...3.5.14&idno=49
http://www.befa.org/pub/49_CFR_Part_1552.html