问 https://groups.google.com/forum/#!forum/stanfordmathcircle
"...
(8) no word yet on AMC 8 for this year, but we do expect to offer the contest at Stanford for students who do not attend a school that offers it. Stay tuned, I should be able to confirm the details of this by mid-October."
You should be able to participate AMC tests after registration or just show up (space permitting)
