Where to find easy research topics any student could write about?
When I have taught research methods for undergraduate work, I find that it is best to give the students a lot of freedom while still requiring acceptance for the topics. I do not think giving a list of acceptable topics is the way to pique the interest of students.

It is better in my experience to guide them and let them know that they know their field better than anyone outside of that field, so they are capable of finding a suitable topic by themselves.

I have had students who choose "I want to study the effect of someone smiling at you." It could be an interesting topic but, since my students are all business majors, I give them the restriction is that it must be related to business. When they submit this topic, I hand it back and ask them "How does this relate to business as I said all research in this module must?"

I guess I could provide them a list but I really think that will just end up limiting them. Better to coax them out of their shell and get them to really start thinking and choosing and living with the consequences of their decisions.