Mrs Liddell took what she called the "unusual" step of writing to every secondary head this week offering further reassurances on Higher Still, although they largely reiterate those already given. She has asked that her letter be circulated to school staff.
The Minister repeated her determination to start implementing Higher Still from August 1999. While she acknowledged that "radical change is seldom easy," she warned the unions: "It is in nobody's interest - least of all the pupils - to contemplate any disruption of this important reform."
Mrs Liddell begins her letter by outlining the "extra resources and extra time" announced last week, before clarifying the Government's position on other issues:
* Phasing She confirmed that the first priority is to replace the existing Highers, where the course content for most subjects is little changed, after which the Advanced Higher will be introduced from August 2000.
Beyond that the pace of change will be up to schools and colleges to decide "in the light of likely demand and available resources". National Certificate modules will continue to be available as Access and Intermediate courses are phased in.
A "reasonable expectation" is that all components of Higher Still should be phased in within three to five years.
* Assessment Internal assessments "are designed to reflect typical learning activities and in most cases should form part of normal course work". The number of assessments in English was reduced in March from eight to six in recognition of the heavier initial load compared with other subjects. Additional training for principal English teachers will be run in October, on top of the November staff development days for all principal teachers.
Mrs Liddell adds: "As unit assessments will replace most of the ongoing assessment of classwork in S5 and S6, the National Assessment Bank removes the need to prepare assessments for class use. Many teachers may also find that they prefer to use internal assessment evidence as a basis for prediction and appeals, saving time in setting and marking prelims.
"NAB tests will provide teachers with clear justification for decisions which have been reached about a student's performance. The NAB is a resource which teachers have never had before, and should greatly ease the task of assessment - and help ensure common standards across Scotland."
* Reassessment The Minister supports the need to restrict reassessments of units within courses. The "Managing Assessment" guidance recommends no more than the original assessment and one reassessment. But even one unsuccessful reassessment would raise the question of whether the student was taking the course at the correct level, whereas Higher Still is designed to match students to appropriate courses.
* Multi-level teaching This is "not a new issue, especially for smaller schools or minority subjects. Where teachers are already dealing with groups working at more than one level, the support materials should make classroom management and delivery easier.
"But no school will be expected or need to provide all subjects at all levels. And schools may wish to consider other options for small groups such as inter-school or school-college partnerships."
* Information technology. Guidance on "baseline IT requirements" has been issued but schools which can demonstrate they need to spend more to get there will be supported by the additional funds announced last week.
* Support materials Mrs Liddell recognises the importance of "timeous distribution" and expects the Higher Still Development Unit to stick to its production schedule. Over the next few months "an abundance of materials" will be arriving in schools in addition to the course arrangements documents, subject guides and manuals on assessment and core skills already issued.
The Scottish Qualifications Authority will step up the distribution of NAB packs from November, with materials for Intermediate 1 and 2 and for new Higher courses. The final version of guidance on Scottish Group Awards will be issued next month and further information on core skills in December.