New semester woes

Students are now comfortable with using the technology to enhance their learning.  They are finding different ways to stay engaged without my direct instruction.  So why the woes? The woes are coming from me dealing with multiple approaches.  You would think this a great thing and I actually do think its great. The real struggle is how to encourage those sitting right next to each other to defend their approach as 1)okay to be different, and 2) correct in their thinking.  Since we still have most students believing since their is only one right answer then there must only be one right way to get there.  WE all know this is untrue so my woe is how do I let students know that is okay to approach it differently?