One of the most wellknown guidelines for achoondroplasia children was published in 2005 in Pediatrics Journal. You can read it on: http://pediatrics.aappublications.org/content/116/3/771.full

Height for males with achondroplasia (mean ± 2.8 standard deviation) compared with normal standard curves.

Height for females with achondroplasia (mean ± 2.8 standard deviation) compared with normal standard curves.
In this link http://pediatrics.aappublications.org/content/116/3/771/T1.expansion.html you can view the table with the health supervision steps, from neonate age until adolescence.