Blocking reports for assignments from students

I assign my students about 6 skills a week. Since last year, some students will answer all the questions in a skill wrong several times. They will then look at the report for that assignment and write down the questions with their answers. They can then answer the questions and pass the skill. Is there any way to block the report from students? I talk to them when I catch them. Writing down all the questions and answers seems like so much more work than just learning how to do the math, but some students think that it's worth it.