We usually recommend that once your book is all published and professionally printed it's time to start promoting your book far and wide... usually school author visits are a brilliant way to sell high quantities of your book and promote it at the same time.
Grab your phone, download a video making app and video yourself reading your book. Think of things that will make it fun and interactive for any child watching... Upload this to your website alongside your worksheets, to make it as easy for a parent or teacher to download and use.
Need an idea of how it looks... here is mine - however ignore the first minute or so... I sound really nervous! haha - I hate the 'hellooo'.