Safe way to organise kids penpals?

My eldest would like to improve her French by having a penpal

Her school doesn't seem to have any existing arrangements so I wondered what others might have used - and been happy with

There are a fair few online things but very wary of using them with my children - once it is set up it would be nice to relax and let her get on with it rather than have to police things

Did u manage to find anything love xx