Book Builder allows you to add three coaches to each page. You have a choice of adding one of the animated coaches and typing a script to be read by text-to-speech or creating your own agent by uploading any image and scripting and recording human voice. 

The create-your-own agent allows the author to include a picture of an object or person that is relevant for that child making the coaching more powerful. In addition, the ability to record human voice rather than using computer voices creates a natural model of good prosody that is not possible when using computer voices alone. The picture below is the area where you can name and create your own agent.

create your own coach authoring box
The image includes three boxes. The box on the left is a pull down menu to number the position of the coach. The middle box includes a question mark. The fox on the far right is a place to type the coach\'s name.