I have quite fair hair so it wasn't a really big deal ... my sister (much darker hair) started using Nair with our parents' permission from maybe 14 years old.

Other girls at my school started shaving or waxing by grade 4-6. Most were by year 7.

By the time arm pit hair came in, basically everyone shaved or waxed both!

And quite a few girls were doing their bikini line by year 8 or 9.