The Federation of North Wales Secondary School Head Teachers has put out a statement about Thursday's AS and A Level results.
It says: "We cannot over-state how disappointed, confused and concerned we are about the A-level and AS results our young adults received today.
"Although the headline data for Wales shows slight improvement, this is not a full reflection of the reality in schools. There are huge disparities in the outcomes of individuals which we cannot track, justify or explain. Pupils’ grades have moved up and down in ways we do not understand.
"As schools, we were asked to consider all our internal and external testing data to create rank orders of learners’ centre assessed grades. We did this with professionalism and fairness to the students we have supported for the last 7 years. This data in many areas has been dismissed, devalued and discounted. Our rank orders have been overlooked and students moved within them making the allocation of grade impossible to fathom and unfair.
"Many universities have downgraded their offers with the absence of international students, resulting in more available places, so many of the young adults involved will thankfully be able to attend the university of their choice. However this is not enough.
"Our pupils’ grades will be with them for the rest of their lives, they will be on their CV for ever. COVID-19 has already disadvantaged them, but life after COVID, within a recession-hit country, means their outcomes will be even more important than ever as they enter a challenging job market. Our students have worked for these grades and deserve them; an algorithm that dismisses this is immoral. If there was ever a time for trust it was now.
"As professionals, we were promised that any anomalies in school data would be discussed, to allow schools to provide the evidence to justify the centre assessed grades. This had not happened - we have been given no opportunity to provide evidence and no conversations have taken place. This has been a statistical model, over reliant on AS outcomes and historical data, and dismissive of the opinion of a profession who supported their students over many years.
"We were grateful for the WJEC announcement about the review of the appeals system as currently it is unworkable and inhibits our ability to challenge the unfairness of these outcomes. The A-level results day is usually one of the happiest of the year. This year our children were hurt, confused and left wondering what had gone wrong, just as we are.