The Wildlife Trusts’ annual nature challenge to do one ‘random act of wildness’ every day, for 30 days in June.
https://www.wildlifetrusts.org/30dayswild
See also a multilingual version of 30 Days Wild, suitable both for children growing up multilingual, and for those learning another language at school. Each day brings an idea for an activity, and encourages multilingualism and language learning.