All of these can be part of an overall project as long as they are used to answer an original question. Creativity promotes efficient and reliable problem solving. Usage of large, impressive equipment or the con struction of a special device is by itself not as important as the question being asked. A well-defined project has a natural end point and should not be the type of investigation that can take a career to work through. Also, the problem should not be so simple that the solution is obvious or trivial.
Good students can show surprisingly advanced skills.
If the student knows their project and subject well, then credit them for their skill level. Again, parental help that is appropriate for the age level does not lessen the skill involved in the project. Assistance does not automatically lessen the skill involved. Take the student's age into account in making this assessment. Adult supervision, by itself, does not indicate a low skill level.