(Edited by HansV to provide link to post – see Help 19)
Whilst it has been covered elsewhere to deal with more complex alphanumeric sorting, I found the following MS Knowledgebase site helpful.
How to Sort Alphanumeric Strings Based on Their Numeric Portions
In my example I have a list that includes the simple letter ‘P’ for Prep year and the numbers 1 to 7 for the class year level. Even with the data type set to Text and a simple ascending sort applied, the ‘P’ would always end up at the bottom of the list. But the code in the link resolves that even though my list does not have a ‘Prefix’ or ‘Suffix’. This solution was based directly on an question posed on sorting (post 396,675).