Crestline is located at GR1.(34.242456, -117.289899)
Lake Gregory is located in Crestline.
As of the censusGR2 of 2000, there were 10,218 people, 4,000 households, and 2,767 families residing in the CDP. The population density was 362.9/km² (940.4/mi²). There were 6,695 housing units at an average density of 237.8/km² (616.2/mi²). The racial makeup of the CDP was 88.04% White, 0.79% African American, 1.13% Native American, 0.59% Asian, 0.19% Pacific Islander, 4.98% from other races, and 4.29% from two or more races. Hispanic or Latino of any race were 10.46% of the population.
There were 4,000 households out of which 33.4% had children under the age of 18 living with them, 53.0% were married couples living together, 10.6% had a female householder with no husband present, and 30.8% were non-families. 24.7% of all households were made up of individuals and 6.6% had someone living alone who was 65 years of age or older. The average household size was 2.55 and the average family size was 3.04.
In the CDP the population was spread out with 27.8% under the age of 18, 6.3% from 18 to 24, 27.7% from 25 to 44, 29.1% from 45 to 64, and 9.1% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 100.6 males. For every 100 females age 18 and over, there were 97.0 males.
The median income for a household in the CDP was $44,257, and the median income for a family was $51,655. Males had a median income of $48,772 versus $28,750 for females. The per capita income for the CDP was $20,987. About 6.6% of families and 8.9% of the population were below the poverty line, including 10.7% of those under age 18 and 4.8% of those age 65 or over.