Judicial review allows individuals, businesses, and other groups to challenge the lawfulness
of decisions made by Ministers, Government Departments, local authorities and other public
bodies. The main grounds of review are that the decision maker has acted outside the scope
of its statutory powers, that the decision was made using an unfair procedure, or that the
decision was an unreasonable one. The Human Rights Act 1998 created an additional
ground, making it unlawful for public bodies to act in a way incompatible with Convention
rights.
...
Judicial review is not concerned with the ‘merits’ of a decision or whether the public body
has made the ‘right’ decision. The only question before the court is whether the public
body has acted unlawfully. In particular, it is not the task of the courts to substitute its
judgement for that of the decision maker. The courts would traditionally only intervene
where a public body had used a power for a purpose not allowed by the legislation
(acting ultra vires) or in circumstances where when using its powers, the body has acted
in a manner that was obviously unreasonable or irrational. In cases where there is a real
unfairness, the courts may now be willing to intervene where the public body has made a
serious factual error in reaching its decision.
http://www.parliament.uk/commons/lib/research/rp2006/rp06-044.pdfI wouldn't have thought he stands a chance of succeeding. The Department of Education has always had the ability to produce and distribute educational material on subjects, and I can't see any human rights aspects to this. Sending out the packs is not 'irrational' - with the huge weight of scientific opinion behind it, it's clearly reasonable (sending out global warming denial information might make for an interesting case, though - how many dissenting scientists would it take to stop denial being unreasonable?)
The normal reply to things like this is "you don't like it? Then vote for another party at the next election".