Childrens picture book and sound effects made by my little girl. What the Ladybird Heard by Julia Donaldson. Drafting Materials And Tools Its Uses Functions It is common to see the reliability of instruments used in published science education studies framed in terms of a statistic known as Cronbachs alpha Cronbach 1951Cronbachs alpha has been described as one of the most important and pervasive statistics in research involving test construction and use Cortina 1993 p98 to the extent that its use in.