"Students give less time to homework, school assignments, preparation for academic contests and tutorial classes than to leisure activities like watching television," Dr Sakchai Niranthawee told a seminar on students' educational responsibility.

Sakchai has taught at the Srinakharinwirot University's Faculty of Education and conducted the survey, which questioned 12,158 students.

The survey found that reading, listening to the radio, playing sports, chatting on the phone and doing household chores were among the most common activities outside class.

Sakchai said the survey also revealed that students were given lots of homework and school assignments to do after class, and thus they preferred to keep their free time for leisure rather than learning.

"The education system should provide opportunities for students to explore their own abilities, interest and needs," he said.

Dr Lekha Piya-achariya, an adviser to the Office of the Education Council, said the amount of homework set by teachers had prevented students from learning how to manage their time and learning more on their own.

"Time management is one of the necessary skills in life," she said.

Lekha suggested Sakchai's findings could be used to encourage students to increase their knowledge.

"If students spend a lot of time watching television, then there should be good programming. Television programmes can give knowledge. Good television programmes can be used as teaching materials," she said.