I only found information about these challenges in Finnish but do feel free to join if you are up for it!
On 6.9 the Nordic Ecolabel, the Swan, is organizing (at least in Finland) the No Make-up Day. The idea is to go the whole day without make-up to support and inform about eco-cosmetics. Let's hope I don't wake up with a big spot on the nose!
The other challenge is for a bit longer, the challenge is to eat at least 500 grams of locally (nationally) produced greens per day during the period 10.9-19.9. I'll try to stick to eating at least 500 grams greens per day but let's see if I will manage to find locally produced that is also eco-friendly. We'll see, I will try to update on the challenge here.