Many conditions and diseases can significantly affect a child’s health and ability to function successfully in school. Most health impairments are chronic conditions; that is, they are always present, or they recur. By contrast, and acute condition develops quickly with intense symptoms that last for a relatively short period of time. To be served under the OHI category, the student’s health condition must limit strength, vitality, or alertness to such a degree that the student’s educational progress is adversely affected. More than 200 specific health impairments exist, and most are rare (Turnball et al., 2004).