This is the start of a road map for the effective introduction of inquiry-based learning in chemistry. Advantages of inquiry-based approaches to the development of scientific literacy are widely discussed in the literature. However, unless chemistry educators take account of teachers' reservations and identified disadvantages such approaches will never have the place they deserve in the everyday teaching of chemistry. If circumstances do not allow for complicated and open-ended inquiry tasks, simpler and more structured inquiry-based tasks may be used. As a first step, teachers could be asked to modify and adapt established "step-by-step" instructions to practical activities which require some stages to be designed by the students. If this happens only a few times in a school year the question arises about its effectiveness to develop experimental design skills and to reinforce knowledge and ideas taught in chemistry lessons. The present study describes the results of an empirical research project aimed to finding the answer. Modification of step-by-step practical activities as described requires limited time and effort, yet the results suggest that many students benefit from this approach.