A parents' concern group seeking to delay the introduction of national-education lessons in schools is urging supporters to write to their children's schools to voice their opposition.
It also hopes they will write to the schools they attended as children.
The group hopes to pressure the government to put off the launch of the curriculum, which primary schools can choose to begin teaching from next month.
Eva Chan Sik-chee, a co-founder of the Parents Concern Group on National Education, said the next phase of their campaign was aimed at putting pressure on schools, so they 'can clearly hear the opposition voices'.
She said it was time to tell school principals that gaining 'knowledge about China goes beyond [instilling] a narrow sense of nationalism'. Critics of the curriculum fear pupils will be 'brainwashed' by lessons praising the Chinese Communist Party.
The Education Bureau had not listened to public opinion, the parents' group said, citing remarks to parents by education minister Eddie Ng Hak-kim on the eve of last month's march opposing national education, in which up to 90,000 people took part.
Ng said the protest would have no impact on plans to introduce the subject in primary schools in September. It is due to become compulsory in public primary schools in 2015 and in secondary schools in 2016.
On its newly launched website, http://parentsconcern.hk , a sample letter is available for parents to use. It includes five questions, among them, 'What year will the school introduce the subject?' and 'What teaching materials will be used?'
Chan said: 'I hope we can kill two birds with one stone - we can put pressure on the schools and we can get a clearer picture of the implementation of the subject.'
She said Ng refused to tell them how many schools planned to start teaching the subject next month, so the group had to obtain the information with parents' help.
After analysing the data, red flags, representing schools that will introduce the subject, will be shown on an electronic map on the website.
Faced with mounting public pressure, many school-sponsoring bodies have said they will not launch the subject next month.
However, a secondary school teacher, who refused to be named, wrote to the group, saying that schools run by various organisations had been embracing national education for some time. 'Why do schools respond in such a positive way?' the teacher wrote. 'The reason is simple - apart from pro-Beijing schools, which are willing to [embrace the subject], other schools face the threat of education reforms, school closures and external evaluations.'
Meanwhile, the Education Bureau said its contracts with the National Education Services Centre and the National Education Centre ended on June 30 but that this had nothing to do with a controversial national-education textbook the services centre published.