Is there evidence in the education literature to support or refute the claim that students who are given problems without solutions to work out on their own do better on different problems in the future (assuming that they took the time to do the problems)? Does it matter if they get the problems correct/incorrect?
I know there is evidence that worked examples help (Sweller and Cooper in 1985 comes to mind as the first reference point). However is there benefit after providing worked examples to provide non-worked examples? Has there been any research justifying this?
The key here is has someone actually done the research supporting this. I do believe that not seeing answers to everything helps but I don't have proof of this.