Students App

This is my attempt at the code challenge.

Discussion

This solution uses .NET 8.0.
The approach I used was a rich domain model based, with class objects with its own behavior and validations. There is a School class which is the main class and is in charge of perform all the necessary school operations, such as register a new student, a new course and a student in a course. The student class inherits from a Person class that has the name and the age, and the course class that saves most relevant information about the course object and implements a payment gateway for each student registration process.

Install .NET 8 SDK (8.0 version)
Run dotnet test to execute all the unitary tests of the project.
If it's required, you can run a specific test of any test class, running dotnet test --filter "FullyQualifiedName=StudentsApp.TestClass.Test", where TestClass is the desired test class and Test the desired test function of that class. e.g: dotnet test --filter "FullyQualifiedName=StudentsApp.MainTest.Main_Succesfully".
The MainTest.cs has the principal test which succesfully executes a complete flow of the application (also shows a list of the students with their courses between a range of dates), but if it's necessary you can check any of the ./tests classes that have all the individual steps of the application with succesfull and invalid cases.

If you have an issue running the dotnet test command with a message about verifying workloads, first run dotnet workload update (with sudo if necessary).

The time invested for this project was about 3 days (4 or 5 hours per day)