Earn via answers for homework is a nice earning method. If you are active in yahoo answer, HomeworkMarket is similar platform but I can pay you as people ask for good answer by paying.
For more difficult question, more rewards for your answer. The platform encourage you to provide good service that the customers will find you again in the further that you can earn much more.
For the educational view, people may think that is a kind of cheating that helps students to score marks without doing anything things. Indeed, to score high mark, the students also need to check the content of the project. If they know how to figure out it is a good project or not, they indeed have some sort of standard to that topic too. As the customers need to provide detail information and idea, the platform is providing a WIN-WIN platform for people who like to answer.