Articulation

Articulation is the way we speak.  This includes all of the sounds we say individually, and as a group.  It is very common for children to have difficulty making some sounds.  That's why I have a job!  Articulation is disordered when a child continues to say a sound wrong past the expected time frame (see below).  Here is the definition of Articulation Disorders from ASHA's website.

Age at which 85% of GFTA-2 Standardization Sample Correctly Produced the Consonant and Consonant Cluster Sounds in the Initial Position of words (p. 56)

2  /b/, /d/, /h/, /m/, /n/, /p/

3       /f/, /g/, /k/, /t/, /w/

4       /kw/

5  /ch/, /dz/ (judge), /l/, /s/, /sh/, /j/ (yellow), /bl/

6  /r/, /v/, /br/, /dr/, /fl/, /fr/, /gl/, /gr/, /kl/, /kr/, /pl/, /st/, /tr/

7  /z/, /sl/, /sp/, /sw/, /th/ (this), /th/ (thanks)

Here is a treasure trove of articulation handouts, suggestions for remediation, and more from Caroline Bowen!
Here are the specific resources for some of the most commonly misarticulated sounds:
Initial /k/ words
Initial /g/ words
Initial /l/ words
Initial /r/ words
Initial /s/ words
Medial /s/ words
Final /s/ words
Initial and final /z/ words