Readability plays a vital role in the transfer of knowledge or information. This is especially true for children who are more than anyone gaining new knowledge every day, yet their reading abilities are still in active development. Although readability assessment of children's literature is an active topic of research in many different languages, research into the assessment capabilities of well-known Dutch traditional readability formulas on texts aimed at Dutch children remains in its infancy. In this paper, we explore the performance of four well-known Dutch traditional readability formulas when applied to different types of texts targeting Dutch children. More specifically, we examine the applicability of the Flesch-Douma, Leesindex A, CLIB and CILT formulas on excerpts of school materials, books, and media for children aged 6-14 years old. Outcomes from this empirical exploration reveal that the readability formulas do not perform similarly across reading materials. As a result, choosing a readability formula based on both the type of reading material and a child's age can improve the readability estimation, which in turn can help connect children to understandable resources.