The message conveyed in the lesson "Indigo" is wise and courageous leadership can resolve any problem.

Explanation:
In the lesson "Indigo," the central theme revolves around the issue of indigo cultivation and the exploitation of the indigo farmers by the British. The story is set in the backdrop of the Indian freedom struggle, where the British had imposed heavy taxes on the indigo farmers and forced them to cultivate indigo instead of food crops. This led to widespread poverty and hunger among the farmers.

The protagonist of the story, Rajkumar Shukla, represents wise and courageous leadership. He takes it upon himself to fight for the rights of the indigo farmers and approaches Mahatma Gandhi to seek his help. Rajkumar Shukla's determination and courage to stand up against the oppressive British rule and fight for the rights of the farmers demonstrate the message of the story.

Through his relentless efforts, Rajkumar Shukla convinces Mahatma Gandhi to visit the Champaran district and witness the plight of the indigo farmers firsthand. Gandhi's arrival in Champaran brings hope to the farmers and inspires them to stand up against the British. Gandhi, with his wise and courageous leadership, leads the farmers in a non-violent protest and successfully resolves the issue of indigo cultivation.

The lesson emphasizes the power of wise and courageous leadership in bringing about positive change and resolving problems. It highlights the importance of standing up against injustice and fighting for the rights of the oppressed. The story also showcases the effectiveness of non-violent methods in achieving social and political goals.

In conclusion, the message conveyed in the lesson "Indigo" is that wise and courageous leadership, represented by Rajkumar Shukla and Mahatma Gandhi, can resolve any problem. It encourages individuals to take a stand against injustice and work towards a better future.