Ysgol Dyffryn Nantlle

78 per cent of pupils come from homes in which Welsh is the main language of the household. Nearly all pupils are able to speak Welsh to first language level.^{[citation needed]}

On the school's badge, the words 'Delfryd Dysg Cymeriad' are inscribed, which translates to "The ideal of education is to build character" or more concisely "Education Builds Character". The school badge was devised by a former art teacher at the school, John Davies.^[3]

There are four registration classes in each school year, Y, D, N and P. There are also four school houses, Dulyn, Silyn, Llifon and Llyfnwy, which draw their names from local rivers and lakes. Pupils are allocated in one each of the four houses when enrolled in year 7. School houses compete annually in the sports day and in the historic school eisteddfod.^{[citation needed]}

Following the end of year 11, the school provides pupils with the option of returning to the school for sixth form (years 12 and 13) instead of attending college or an apprenticeship.^[4]

The school encountered controversy in 2021 when the standing headmaster, Neil Foden, brought in a policy to refuse to provide school meals to children with any debt for school meals. The school later changed its policy after a major backlash including criticism from footballer and school meals campaigner Marcus Rashford.^[5]

• Bryn Fôn
• Sir Bryn Terfel Jones^[6]
• Dafydd Glyn Jones
• R. Williams Parry
• Elan Closs Stephens
• Angharad Tomos
• Betty Williams
• Olwen Williams
• Owain Fon Williams

53°03′17″N 4°16′44″W / 53.0547°N 4.2789°W / 53.0547; -4.2789