You can write in your Schooltas books by using the text tool. The text tool is located in the upper right corner of your book. Click the "A|" sign to activate the tool.
Once you've activated the tool you can click anywhere on the page to open the text box. Once the box is active, you can start typing.
To move the text box on the page you can drag the blue navigation button in the upper left corner of the box. If you want to delete the text box, you can press the black "x" in the upper right corner of the text box.
You can also change the font size.
When you're done typing, simply press the "done" button at the top of your screen.
To add drawings to your book, click the drawing symbol:
Click on the page to draw on it. When you're done drawing, click "done".