My First Slide-Out Book of Numbers is designed by early childhood experts to teach your child to count to ten. Pull the tab and the picture magically changes for double the fun. My First Slide-Out Book of Numbers is part of the award winning Early Start Active Reading series. Active Reading prompts at the bottom of each page help you engage your child in conversation in order to promote language and cognitive development.My First Slide-Out Book of Numbers is designed by early childhood experts to teach your child to count to ten. Pull the tab and the picture magically changes for double the fun. My First Slide-Out Book of Numbers is part of the award winning Early Start Active Reading series. Active Reading prompts at the bottom of each page help you engage your child in conversation in order to promote language and cognitive development.