Lagunitas-Forest Knolls is a census-designated place, composed of two unincorporated areas in the western half of the San Geronimo Valley in Marin County, California, United States. It is located to the west of San Geronimo and Woodacre. The population was 1,924 at the 2020 census.
According to the U.S. Census Bureau, the CDP has a total area of , all land.<br> 1860–1870 1880-1890<br> 1900 1910 1920<br> 1930 1940 1950<br> 1960 1970 1980<br> 1990 2000 2010<br> 2020
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Lagunitas-Forest Knolls first appeared as a census designated place in the 1980 United States census.
!Pop 2010
!style="background-color: #ffffb3;" |Pop 2020
!% 2000
!% 2010
!style="background-color: #ffffb3;" |% 2020
|-
|White alone (NH)
|1,599
|1,583
|style='background: #ffffe6; |1,543
|87.14%
|87.03%
|style='background: #ffffe6; |80.20%
|-
|Black or African American alone (NH)
|26
|25
|style='background: #ffffe6; |19
|1.42%
|1.37%
|style='background: #ffffe6; |0.99%
|-
|Native American or Alaska Native alone (NH)
|11
|3
|style='background: #ffffe6; |12
|0.60%
|0.16%
|style='background: #ffffe6; |0.62%
|-
|Asian alone (NH)
|25
|10
|style='background: #ffffe6; |38
|1.36%
|0.55%
|style='background: #ffffe6; |1.98%
|-
|Native Hawaiian or Pacific Islander alone (NH)
|2
|1
|style='background: #ffffe6; |0
|0.11%
|0.05%
|style='background: #ffffe6; |0.00%
|-
|Other race alone (NH)
|14
|9
|style='background: #ffffe6; |21
|0.76%
|0.49%
|style='background: #ffffe6; |1.09%
|-
|Mixed race or Multiracial (NH)
|56
|55
|style='background: #ffffe6; |137
|3.05%
|3.02%
|style='background: #ffffe6; |7.12%
|-
|Hispanic or Latino (any race)
|102
|133
|style='background: #ffffe6; |154
|5.56%
|7.31%
|style='background: #ffffe6; |8.00%
|-
|Total
|1,835
|1,819
|style='background: #ffffe6; |1,924
|100.00%
|100.00%
|style='background: #ffffe6; |100.00%
|}
2020 census
As of the 2020 census, Lagunitas-Forest Knolls had a population of 1,924. The population density was . The racial makeup of Lagunitas-Forest Knolls was 1,589 (82.6%) White, 20 (1.0%) African American, 22 (1.1%) Native American, 38 (2.0%) Asian, 0 (0.0%) Pacific Islander, 54 (2.8%) from other races, and 201 (10.4%) from two or more races. Hispanic or Latino of any race were 154 persons (8.0%).
The census reported that 99.3% of the population lived in households, 0.7% lived in non-institutionalized group quarters, and no one was institutionalized. 0.0% of residents lived in urban areas, while 100.0% lived in rural areas.
The age distribution was 287 people (14.9%) under the age of 18, 87 people (4.5%) aged 18 to 24, 413 people (21.5%) aged 25 to 44, 607 people (31.5%) aged 45 to 64, and 530 people (27.5%) who were 65years of age or older. The median age was 51.3years. For every 100 females, there were 96.5 males, and for every 100 females age 18 and over there were 96.0 males age 18 and over.
2010 census
At the 2010 census Lagunitas-Forest Knolls had a population of 1,819. The population density was . The racial makeup of Lagunitas-Forest Knolls was 1,658 (91.1%) White, 26 (1.4%) African American, 11 (0.6%) Native American, 11 (0.6%) Asian, 1 (0.1%) Pacific Islander, 43 (2.4%) from other races, and 69 (3.8%) from two or more races. Hispanic or Latino of any race were 133 people (7.3%).
The census reported that 99.5% of the population lived in households and 0.5% lived in non-institutionalized group quarters.
There were 817 households, 213 (26.1%) had children under the age of 18 living in them, 354 (43.3%) were opposite-sex married couples living together, 86 (10.5%) had a female householder with no husband present, 40 (4.9%) had a male householder with no wife present. There were 57 (7.0%) unmarried opposite-sex partnerships, and 10 (1.2%) same-sex married couples or partnerships. 259 households (31.7%) were one person and 45 (5.5%) had someone living alone who was 65 or older. The average household size was 2.22. There were 480 families (58.8% of households); the average family size was 2.78.
The age distribution was 342 people (18.8%) under the age of 18, 94 people (5.2%) aged 18 to 24, 339 people (18.6%) aged 25 to 44, 808 people (44.4%) aged 45 to 64, and 236 people (13.0%) who were 65 or older. The median age was 48.9 years. For every 100 females, there were 94.8 males. For every 100 females age 18 and over, there were 97.5 males.
There were 897 housing units at an average density of , of which 66.7% were owner-occupied and 33.3% were occupied by renters. The homeowner vacancy rate was 1.6%; the rental vacancy rate was 3.2%. 71.4% of the population lived in owner-occupied housing units and 28.1% lived in rental housing units.
Education
The CDP is served by the Lagunitas Elementary School District and the Tamalpais Union High School District.