The Kenya Certificate of Secondary Education (KCSE) written examinations begin tomorrow.
They will then sit mathematics paper one and English comprehension.
Practical examinations and oral tests for French, German, Arabic and Kenya sign languages began on February 28.
A total of 831,015 candidates registered for the examination to be administered at 10,413 centres.
Last year, some 752,981 students sat the papers at 10,437 stations.
The number has increased by 78,034 this year, a 9.39 per cent rise.
Education Cabinet Secretary George Magoha warned teachers and candidates against cheating and other malpractices during the tests.
“I urge teachers involved in the administration of the Form Four national examination not to be tempted to use phones or cheat,” Prof Magoha said.
The Kenya National Examinations Council (Knec) released guidelines on the administration of the tests.
In the guidelines released by Knec Chief Executive David Njengere, schools must upload marks for the subjects with a project by January 31.
To curb cheating and other malpractices, Dr Njengere said candidates would not be allowed to leave the exam room before the end of the period allocated to the paper, except with special permission from supervisors.
There will be no communication in the examination room and neither will outsiders be allowed into the centere during the tests.
Cases of university students impersonating KCSE examination candidates have been recorded in the past.
Last year, some 27 officials were relieved of their duties as centre managers, supervisors or invigilators over allegations of violating rules on the administration of the examinations.
Some 37 civilians, including three university students and two businessmen, were arrested for assisting in irregularities.
Those arrested were accused of opening examination materials before time and sharing the information with students through social media.
“Any misconduct or causing of disturbance in or near the examination room will be treated as an irregularity,” the guidelines read.
“For practical papers to be taken in shifts, candidates taking the examination must avail themselves for confinement. Any candidate who does not present him/herself for confinement will have committed an examination irregularity.”
Dr Njengere also warned candidates against using cell phones and other electronic communication devices.
