Check these links out if you are worried about a test coming up! These were extremely helpful to me:
THC Detection Times in Occasional Smoker
http://www.erowid.org/experiences/exp.php?ID=37341
20 Drug Testing Information
http://www.erowid.org/psychoactives/testing/testing.shtml
HOW TO PASS A DRUG TEST - GENERAL TIPS
http://www.alwaystestclean.com/drug_test_advice.htm
THC Detection Times in Occasional Smoker
http://www.erowid.org/experiences/exp.php?ID=37341
20 Drug Testing Information
http://www.erowid.org/psychoactives/testing/testing.shtml
HOW TO PASS A DRUG TEST - GENERAL TIPS
http://www.alwaystestclean.com/drug_test_advice.htm