Earth Day happens in April every year (since 1970!!!). It gets bigger and bigger, although it is amazing that it has taken over 50 years to get such traction. One way in which we see its impact expanding is the creation of Earth Month by the Center For Environmental Justice And Sustainability at Seattle U. This gives a longer window for people to take action and establish and/or join a varirty of events across different focuses, often in an SDG context.
Check it out for how you can be involved:
Genius is one percent inspiration and ninety-nine percent perspiration.