Q: While I understand that every case is different, as a general rule, at what age do you consider it appropriate to target R when it is the only error?

I have taught R to one- and two-year old children, so I know it is possible to do very young. However each therapist must address this question relative to his or her employment situation. Therapists in private practice often see these kids at 4 and 5 years of age. Therapists in the schools usually have district-wide guidelines they have to follow that restrict them from seeing these kids before age 7, 8, or even 9 years of age.

You will have to do what is best for you and your work setting. Many of the old-time SLPs used to go in the classroom to do “Speech Improvement Lessons.” They would lead the whole class in methods to teach all the problematic phonemes, like L, R, S, Th, F and so forth. One phoneme would be taught per lesson, and it would be coordinated with the reading/spelling curriculum. That way the SLP could see which kids responded well to simple general instruction and which might need individual therapy.