Morning: Visit Coaker's Walk for a scenic view of the valley followed by a boat ride in Kodaikanal Lake.
Afternoon: Explore the Pine Forest and Bear Shola Falls, and indulge in some shopping in the local markets.
Evening: Take a dip in the Silver Cascade Falls and enjoy a bonfire night with drinks and music.
Morning: Visit the tea plantations and learn about the tea-making process at the KDHP Tea Museum.
Afternoon: Trek through the Eravikulam National Park and spot some endangered species such as Nilgiri Tahr and Anamudi Peak.
Evening: Visit the Rose Garden and enjoy some local snacks at the nearby tea stalls.
You can also consider visiting Top Station for a panoramic view of the Western Ghats. A side trip to Meesapulimala, the second-highest peak in South India, is also highly recommended.
To maximize your fun, you can go for an off-road Jeep Safari or indulge in some adventure sports such as paragliding and rock climbing.
Lastly, don't forget to try the local delicacies such as Appam, Puttu, and Fish Molly.