This study aims to explore navigation patterns and preferred pages' characteristics of ten secondary school students searching the web for information about cloning. The students navigated the Web for as long as they wished in a context of minimum support of teaching staff. Their navigation patterns were analyzed using audit trail data software. The characteristics of their preferred Web pages were also analyzed using a scheme of analysis largely based on socio-linguistics and socio-semiotics approaches. Two distinct groups of students could be discerned. The first consisted of more competent students, who during their navigation visited fewer relevant pages, however of higher credibility and more specialized content. The second group consists of weaker students, who visited more pages, mainly of lower credibility and rather popularized content. Implications for designing educational web pages and teaching are discussed.