I took classes for a month at Colibri in preparation for moving to Nicaragua. The teachers were intelligent, well-trained, and pleasant. They used a variety of teaching methods (e.g. direct instruction, conversation, reading, audio recordings). They changed my teacher after 2 weeks to broaden my exposure to teaching methods and vocabulary. Students can also request a change of teacher at any time.
My husband and I also did volunteer work at a daycare set up by Colibri. We received a discount on our classes for doing the volunteer work. Through the volunteer work and homestay, we had many additional opportunities to practice Spanish even when we weren't in class.
I appreciated the school's and teachers' willingness to engage, both in conversation and in action, social and political themes relevant to Nicaragua and to the world (e.g. women's rights, the rights of the elderly, environmental protection, education, religion).