In the present study, orthographic metrics for Greek children’s Grade 1 and Grade 2 reading materials were presented. Data for five transparency metrics—three of which being neither feedforward nor feedbackward— were presented and offered for use in the research of children’s reading and spelling acquisition. The analysis demonstrated the complex relationships between metrics and compared the results with those obtained for the English language. The structure of these metrics from a variety of corpus sizes was investigated, and we concluded that large corpus sizes do not necessarily make a substantial contribution to the value of such metrics when compared with smaller samples.