Congratulations on your new appointment. You are right to highlight the importance of capacity to improve, particularly where pupils are underachieving and a school is failing to provide an adequate standard of education. School leaders don’t always realise, as you do, that capacity to improve is more than merely scope for improvement.

Inspectors have to see evidence not just of good intentions but also that changes are having a positive impact. Inspectors will be realistic, however. They will appreciate that change cannot be achieved overnight and they will take account of what could reasonably be expected in the timescales involved. That cuts both ways. Inspectors might reasonably expect a head who has been in a post for years to demonstrate more impact than one who has just started.

Having established that aspirations are not enough, what can you realistically show inspectors? New in post, you will need to show them how you have diagnosed the problems and worked out the potential solutions. Show them, for example, that you have at least formed and tested a hypothesis about why pupils have been underachieving.

Inspectors will look at how you have prioritised the issues you believe to be most pressing, the actions you have initiated and at the way staff have responded to feedback. Looking at pupils’ workbooks can provide early evidence of your actions.

If pupils are underachieving because provision is inadequate but you can demonstrate that the school does now have the capacity to improve, then the school will be given a notice to improve. This means that it will be inspected again in 12 to 16 months’ time. You can expect this second inspection to focus particularly on how well the school has addressed the issues from the previous visit. If the issues have been tackled successfully and the school’s overall effectiveness is at least satisfactory, then the notice will be removed.

Selwyn Ward has been an inspector for 15 years, working in primary and secondary schools. The views expressed here are his own. To ask him a question, email him at features@tes.co.uk.