The age for kindergarten varies by state, but most states require that students be 5 years old by a certain date in the school year, usually August 31 or September 1. However, some states have different cutoff dates, and some states allow districts to set their own age requirements. In general, children must be between the ages of 4-6 to attend kindergarten. Some states and districts have pushed the minimum age to start kindergarten up so that more and more kids are at least 5 years old when they start school. In some states, it is possible to find a 5-year-old and a 7-year-old in the same kindergarten class, while in others, there might be a 4-year-old. Redshirting, or giving children an extra year before starting kindergarten, has become more popular in recent years. Ultimately, the decision of when to start kindergarten depends on the childs readiness and the parents preferences.