As a worker at the hotel, I have to have the expert knowledge of excel and other calculation tools. So, I start learning excel from Chicago computer class (a friend told me about them). They are best in Chicago. I was able to learn about everything in excel in less than a week. And I am using knowledge for more than 5 years. I will give CCC 5 star in teaching, connectivity and organization.
Tip for consumers: Be regular and attentive and always practice.