research method

today I had a difficult day when supervising students in the 500 hours projects. while students do not have formal research methods education, I ask them to choose a method (I propose action research), to define goals, plan, and evaluation issues. Today, 3 weeks before deliver deadline, one group asks me about which method they have used. the leader student tells "we have been looking on the internet, and setting up an open source project", how can we now evaluate it?

I ask them to make an evaluation plan with alternatives.
Let us see.