I thought about that but as uniforms are so cheap now in the supermarket (and really not that bad) I bought the school pini and made a pretty little skirt for my daughter instead, with jazzy spotty fabric, so she has something we both love for the time spent. Unless you have fabric already and are happy to make a pattern (try tracing her old one) the material and pattern will cost more than a high street school pinafore.
I didn't think to mention it but she's seven & wears my size 8 clothes sometimes (she's not fat or anything - just a giant compared to her friends) so high street ones are not really an option as it's age 13 she's outgrowing.
I could unpick the smallest of the three though & add inches to that to make ones to fit.
What fabric would you use? I'm still re-aquainting myself with sewing after ten years not making anything
Yes unpicking one is definitely the way to go rather than buying paper patterns (££). Add to the sides and also the top of the shoulders - a couple of cm's each. Also use some non-stretch cotton tape around the arms and neck or they will grow as you sew and get all out of shape. You want a washable gaberdine / worsted or similar woven fabric. I sometimes use www.myfabrics.co.uk. Depends on where you are based, we also have amazing local shops that sell end-of-line fabrics at bargain prices (Brixton) you might find something similar.