Phase changes in water are experienced in everyday life but students often struggle to understand mechanisms that regulate them. Human thermal comfort is closely related to humidity, evaporative heat loss and heat transfer. The purpose of the present study is to assist students in the evaluation of human thermal comfort. Such a goal is achievable through effective interaction with a set of simple ad hoc computer functions. The currently available version of the functions allows the user to: (i) convert temperature to and from Fahrenheit, Celsius and Kelvin degrees, (ii) convert moisture content to and from absolute humidity, relative humidity and water vapor partial pressure, (iii) calculate the dew point, (iv) evaluate two of the most reliable thermal comfort indices, the New Summer Simmer Index (NSSI) and the Apparent Temperature (AT). A thermal comfort index is an attempt to determine the human-perceived equivalent temperature in order to assess the risk of heat stress. Functions are interconnected so as to be able to calculate the comfort indices starting from moisture content and air temperature. Functions can be used either in interactive mode or by querying an existing database. Easy steps to implement the script on a real database engine are provided so it is even suitable for inexperienced users. Proposed functions have been successfully used as a complement to traditional laboratory experiences at tertiary level. Students' learning was evaluated through the analysis of a pre-post test.