This app is about tracing numbers while collecting cute little fireflies for the jar. This would be pretty easy for a child. I did notice as soon as I opened up the app it would show the volume control. I would suggest putting the parental controls on due to in-app purchases.
The app also has a parent mode, in it the parent can control the sounds (making the sounds go off or on, changing the voice to a male or female, and making the music go off or on), see the progress that the child is making, and make a profile for the child.