Ecotourism and places to visit in Kerala
Before looking at the ecotourism places to visit in Kerala, let's understand what it is. Ecotourism is "responsible travel to natural areas that conserves the environment and improves the well-being of local people" given by TIES (The International Ecotourism Society).
To put it simply, ecotourism is tourism but with respect and discipline towards the destination in a way that is beneficial for the locale. Now you can become an ecotourist too by visiting places that are already made beneficial and disciplinary. And there are many such in our God's own Kerala.

Places to visit in Kerala that are quite Ecotourist
It is not a surprise that Kerala preserves its scenic beauty as it is. Because ecotourism began in Kerala as an experiment too. Adavi Eco-Tourism is a place where the tourists have developed the area in a way that it created new jobs and encouraged locals to accommodate tourists.

Adavi Eco-Tourism
Most of the ecotourism is concerned with rainforests. And Adavi Ecotourism is a rainforest area too. There is a bus to Adavi Eco Tourism from anywhere in Kerala. You book a flight to Thiruvananthapuram and then catch a bus to Konni, the village where there is Eco-Tourism.
You can trek, hike, boat and even spend time in the Konni village with the local accommodation. These benefit the local people as they are guides themselves. And the entire village is maintained clean respecting their region.
Thenmala really defines what ecotourism is. Because it is a dense hilly forest and usually called Honey Hills. There are green bridges made with wood and the entire hike in these honey hills feel refreshing and quite eco-friendly.

Aralam Wildlife Sanctuary
Aralam is as explained a wildlife sanctuary and is maintained in a quite eco-friendly way. You can find deers, foxes, bison, bears and wild cats here. For us to see the animals naturally in their habitat, we also need to maintain the sanctuary as it is.
It is a beautiful experience to visit Aralam. You can book flights to Calicut or Thiruvananthapuram to get to Kerala and go by bus or private vehicles. As there is no accommodation in the wild, you are expected to book hotels in nearby cities or places.

It is also one of the best places to visit in Kerala because of the natural scenic beauty you encounter there. The boathouse of Alappuzha is something everyone travels to Kerala to witness. It is not to be missed even if you usually went to Kerala.
Wrapping Up
There are many other places too but they are right now still being developed as an Ecotourist spot. You can join the NGOs and tourists who are helping to make them such. It is quite a beautiful initiative. Respect nature and it respects you back, they say.