A former head of business studies at a secondary school has been jailed for dealing drugs to students.
Rachel Ryan, 41, who admitted importing and selling tranquilisers, offered one pupil at Banbury Academy a discount for buying more than 100 tablets, police said.
She admitted dealing diazepam, alprazolam and nitrazepam.
Ryan, from Swansea, admitted seven drugs offences and was jailed for 15 months at Oxford Crown Court on Friday.
Police also found heroin in her possession, police said.
She was caught after another teacher saw a student texting in class, seized the phone, and realised they were contacting Ryan about drugs.
Thames Valley Police found she had also been offering valium for sale, as well as ordering class C drugs to be delivered to her address in Banbury.
She was arrested on 24 June last year, and a quantity of heroin was found in her possession. The total street value of the drugs seized was about £1,900.