[blindkid] brailling book question

[Rosina Solano]

I have sorted out some of our print books that we no longer need.  I am going to make braille to go on the pages of the books for kids that could use print/braille books with pictures.  However, I have a question regarding contracted and uncontracted braille.  At what reading level would you change over?  I have several beginning readers and up to some read on your own books, but don't know when to change over the format of braille.  I can't remember what level my sons starting switching.  Hoping someone could help me before I start on these.
 
Thank you in advance;
Rosina