The teachers at Wortley High School suffered from dizziness and headaches after eating the hash cakes, and were taken to hospital for emergency check-ups.
Upon their examination, the doctors suggested that the teachers had probably been drugged with cannabis.
The teachers were discharged from hospital hours later, and they returned to school the following day.
No official complaint about the incident was lodged and no police action taken; consequently, no tests were carried out on the cakes.
Staff at the school are said to have been asked not to accept food from pupils in the future.
"On September 10, two teaching assistants were taken to hospital after eating food taken into school by a pupil which was later suspected of containing an unknown substance. An investigation took place and the pupil was temporarily suspended," the Telegraph quoted a spokesman for Leeds City Council as saying.
"The student in question has not been excluded from education, but is completing her studies at another school in Leeds," he added.
A spokesman for Wortley High School said: "Wortley High School does not condone drugs and was disappointed this incident took place. Following a swift investigation, it took appropriate action which removed the pupil from the school while allowing her to remain in education. The school works hard to educate its pupils about the dangers and implications of drug abuse and will not tolerate any behaviour of this kind."