Technological solutions alone will not be enough to prevent children using the internet to cheat in their coursework, a government adviser has said.
The exam watchdog has warned of plagiarism using the internet
Professor Jean Underwood of Nottingham Trent University says it is up to teachers and parents to show that plagiarism is inappropriate.
The government has asked Professor Underwood to provide technical advice on how to detect internet cheating.
It has commissioned a review of GCSE coursework in each subject.
The move comes after report by the Qualifications and Curriculum Authority said downloading essays from the internet "could not be controlled".
Professor Underwood, an expert in the impact of new technologies on teaching and learning, said less repetitive and more creative questioning would reduce the scope for cheating.
She said the parameters of her study were still to be defined, but she wanted to help find solutions "so that everyone is reassured that coursework is valid, relevant and secure".
Rules should be made clearer, Professor Underwood said.
"We all reject websites which sell essays, but where does that leave us when there are so many help books to get pupils through their GCSEs? Where is the line?"
And parents need to understand that by doing work for their children, or telling them what to include, they are not allowing them to learn effective research - an important skill for later life.
"If a parent helps their child to carry out an efficient internet search, I personally do not see anything wrong in that," she said.
"But downloading five papers from the internet would be a borderline crossed."
She said the government has recognised there is concern and will put down guidelines around February next year.
But it was "all our jobs to collectively show that cheating should not happen".
Teachers have voiced concerns that there are inconsistent guidelines across exam boards regarding how much guidance teachers should give to pupils.
They are also concerned that providing templates and checklists for work leads to "cloned essays" which are difficult to tell apart.
"Templates are worrying, if they lead to the pupil not understanding the material," Professor Underwood said.
The NASUWT teachers' union said it was important to keep the issue of plagiarism in proportion.
But it welcomed the idea of clearer guidelines, but said policing every line of work for plagiarism would "place an impossible burden upon teachers".
Coursework is marked internally within schools, while exam boards call in samples of the work for external checks, known as "moderation".
At GCSE level, it varies from 20% of the overall qualification in double science, to 60% in art and design.
At A-level it can be from nothing to 30%, or 60% in the case of art and design.
Education Secretary Ruth Kelly said coursework should only be used where it is the most appropriate assessment method.
The QCA's report found coursework was a valuable tool to stimulate pupils' own learning, but that the value placed on it by teachers varied between subjects.
Professor Underwood said technology could help ameliorate the problem but was "no quick fix".
She said software already existed to help schools ascertain whether work was the pupil's own.
"It can even be as simple as typing a phrase into Google."
"If a phrase has been plagiarised, sites will bring it up."
"Software is already out there that schools can use, from the Joint Information Systems Committee."
Exam board Edexcel and the Joint Council for Qualifications said they were working with the Plagiarism Advisory Service with a view to rolling out plagiarism detection software.
A JCQ spokesperson said it would reduce the potential to use or re-use work produced by other people.
Professor Underwood said some software could check as well as mark work. But she said some clever students would find ways round such programmes.
"One method used is to translate phrases in papers into a different language and then back into English with a translation tool," she said.
She said that tackling firms providing essays for sale or download would not guarantee children could not access essays, as hackers could still make them available for sale.
"We need to think smart on an academic and technological level," she said
"The internet is a wonderful thing with the power to change lives - but there will always be a downside."