I didn't do any activities like research the summer before senior year?

As a rising senior, I worked as a math tutor over the summer. I didn’t do anything impressive for colleges besides that-- I participated in a tech camp, but other than that, nothing much. Now coming back to school for senior year, a bunch of my peers are discussing how they did research with prestigious universities over the break. One of them merely collected data for a research project, but then again, colleges don’t have to know that, he says. My question is, will my lack of research hurt me in the admissions process? Do my peers now have a huge advantage over me?

There is no point in worrying about this at this point-the summer is over. Focus on writing applications that described what you did and why it meant something to you.