Q: I raised this point with an inspector. I could teach an A-level lesson, for example, that was well planned, delivered with a range of activities and had a plenary showing that the students had learnt, and it could be rated as excellent. However, the inspector would not know if the content was factually wrong. And if what I was teaching were wrong, the learning would be entirely false and would help the students to fail the exam. I received no answer at all - just a bit of bluster followed by a quick moving on of the discussion.
A: It is now actually rather more likely than not that the inspector who observes a lesson will not be a subject specialist. This will be particularly so at secondary and post-16. Of course, it's possible that you could be talking nonsense and an inspector will not pick it up. I dare say that it is even possible for an inspector who is a subject specialist to get things wrong (just as the teacher in your example will have done).
Inspectors generally work on the assumption that teachers know what they are talking about, unless they have evidence to the contrary. The key source of evidence is the outcome for pupils, and especially their exam results. If pupils were being taught the wrong things, those results would be weak, and inspectors - even non-specialists - would look hard to seek out reasons why.
Your example, though, is a good one, and I can't deny that there are sometimes lessons where students are mistakenly fed erroneous information.
Just as there is a thread on the TES online forum on stupid things inspectors have said, I could regale you with some of the many odd things I've observed in lessons over the years, from teachers setting spelling lists that are wrong to instructions about ending sentences with "false stops". I have also seen examples of seemingly well-taught lessons where pupils have learned principles that are just plain incorrect. This admission that the system isn't perfect or foolproof probably won't have reassured you, but at least I haven't blustered.
Q: My child's school is being inspected only 18 months after the last inspection. Why would this happen so soon? It's a primary school and the last inspection was mainly "satisfactory".
A: Since the idea of inspection under the current system is supposed to be that it's a surprise, I would expect - but this is only my surmise - that the initial tranches of schools will include some that were inspected relatively recently, as well as those that guess they are "overdue".
Eventually, once the new system is properly established, schools that are identified as needing more frequent inspection will get inspected more often than others. But I don't think you should read anything into this round of selections other than the fact that there will need to be a degree of randomness to avoid the dates of inspections becoming overly predictable.
Selwyn Ward draws on many years of experience in both primary and secondary schools, but the views expressed here are his own. You can raise any queries or worries that you have about inspection by logging on to the TES website at www.tes.co.uksectionstaffroom