Most of the teachers at my all-girls high school were what would have been termed 'frumpy' back in the day. Even the younger ones - think 'scrubbed' faces and weird, unfashionable clothes and hair styles. It was as though they'd never been in the real world at all, which thinking about it, they probably hadn't.
Being teenage girls and therefore naturally prone to be judgemental about such things, we mocked these teachers behind their backs for the way they dressed and found it difficult to take them seriously. But when I started 6th form we got a new HoD in one of the subjects I was studying. She was early-mid 30s, super glamorous with long hair, lots of make-up and the trendy clothes of the day. In modern terms it was like Kim Kardashian had walked into the school! She was an absolute breath of fresh air and we adored her.
I wore makeup, outside school, from about age 15 but there were other girls who wore it in school and crazy nails etc - I never did any of that, but this glamorous teacher was absolutely my role model, not for the way she looked as such, but for the fact that she seemed so modern and outward looking compared to all the other teachers, who seemed like fossils by comparison. I went on to do the same uni course that this teacher had done (and to wear make-up for most of my life, but that was the influence of my DM and not the teacher).
Sadly your DD is way more likely to be influenced, as regards her appearance, by peers and social media, and just because she isn't into makeup NOW (presumably age 11 ish) doesn't mean she won't be later, especially if she develops acne and gets self-conscious about it. Most young girls want to look nice, it's not a crime. And most would probably prefer a teacher whom they can see as 'relatable'.