| Rank | Average Family Size ▼ | School District / Population |
| 1. | 4.42 | Dietrich School District 314 / 835 |
| 2. | 4.30 | Three Creek Joint Elementary School District 416 / 74 |
| 3. | 4.07 | Murtaugh Joint School District 418 / 1,041 |
| 4. | 4.00 | Snake River School District 52 / 8,072 |
| 5. | 3.94 | West Side Joint School District 202 / 2,658 |
| 6. | 3.92 | Rockland School District 382 / 755 |
| 7. | 3.91 | Sugar-Salem Joint School District 322 / 5,069 |
| 8. | 3.84 | Notus School District 135 / 1,707 |
| 9. | 3.80 | Bruneau-Grand View Joint School District 365 / 2,813 |
| 10. | 3.76 | Melba Joint School District 136 / 3,412 |
| 11. | 3.73 | Shoshone Joint School District 312 / 3,149 |
| 12. | 3.65 | Bonneville Joint School District 93 / 46,626 |
| 13. | 3.65 | Aberdeen School District 58 / 3,645 |
| 14. | 3.64 | Cascade School District 422 / 2,900 |
| 15. | 3.63 | Richfield School District 316 / 1,028 |
| 16. | 3.62 | Wilder School District 133 / 2,934 |
| 17. | 3.62 | Shelley Joint School District 60 / 9,347 |
| 18. | 3.60 | Jerome Joint School District 261 / 19,652 |
| 19. | 3.60 | Cassia County Joint School District 151 / 22,518 |
| 20. | 3.58 | Jefferson County Joint School District 251 / 21,786 |
| 21. | 3.58 | Kimberly School District 414 / 6,350 |
| 22. | 3.56 | Nampa School District 131 / 83,761 |
| 23. | 3.55 | Homedale Joint School District 370 / 5,620 |
| 24. | 3.55 | Caldwell School District 132 / 34,714 |
| 25. | 3.54 | Preston Joint School District 201 / 9,902 |
| 26. | 3.53 | Blackfoot School District 55 / 20,881 |
| 27. | 3.52 | New Plymouth School District 372 / 5,159 |
| 28. | 3.52 | Middleton School District 134 / 15,984 |
| 29. | 3.50 | Minidoka County Joint School District 331 / 20,387 |
| 30. | 3.49 | Madison School District 321 / 33,715 |
| 31. | 3.49 | West Jefferson School District 253 / 2,283 |
| 32. | 3.49 | Ririe Joint School District 252 / 2,588 |
| 33. | 3.46 | Vallivue School District 139 / 37,968 |
| 34. | 3.46 | Avery School District 394 / 567 |
| 35. | 3.44 | Firth School District 59 / 4,216 |
| 36. | 3.43 | Kuna Joint School District 3 / 24,879 |
| 37. | 3.42 | Marsing Joint School District 363 / 4,145 |
| 38. | 3.41 | Gooding Joint School District 231 / 6,739 |
| 39. | 3.39 | Wendell School District 232 / 4,979 |
| 40. | 3.38 | American Falls Joint School District 381 / 6,863 |
| 41. | 3.38 | North Gem School District 149 / 788 |
| 42. | 3.37 | Parma School District 137 / 5,051 |
| 43. | 3.36 | Fruitland School District 373 / 8,103 |
| 44. | 3.35 | Pocatello School District 25 / 76,359 |
| 45. | 3.31 | Castleford School District 417 / 1,555 |
| 46. | 3.31 | Teton County School District 401 / 10,007 |
| 47. | 3.31 | Idaho Falls School District 91 / 55,597 |
| 48. | 3.30 | Lapwai School District 341 / 3,170 |
| 49. | 3.30 | Hansen School District 415 / 1,742 |
| 50. | 3.30 | Payette Joint School District 371 / 9,540 |
| 51. | 3.28 | Filer School District 413 / 6,557 |
| 52. | 3.28 | Mountain Home School District 193 / 23,376 |
| 53. | 3.28 | Meridian Joint School District 2 / 183,387 |
| 54. | 3.28 | Twin Falls School District 411 / 51,076 |
| 55. | 3.22 | Oneida County School District 351 / 4,089 |
| 56. | 3.20 | Weiser School District 431 / 8,482 |
| 57. | 3.20 | Camas County School District 121 / 1,276 |
| 58. | 3.19 | Marsh Valley Joint School District 21 / 6,220 |
| 59. | 3.18 | Culdesac Joint School District 342 / 1,016 |
| 60. | 3.16 | Horseshoe Bend School District 73 / 1,896 |
| 61. | 3.15 | Butte County Joint School District 111 / 2,708 |
| 62. | 3.15 | Fremont County Joint School District 215 / 11,466 |
| 63. | 3.15 | Emmett Independent School District 221 / 16,768 |
| 64. | 3.14 | Buhl Joint School District 412 / 8,922 |
| 65. | 3.13 | Boundary County School District 101 / 10,857 |
| 66. | 3.12 | McCall-Donnelly Joint School District 421 / 6,952 |
| 67. | 3.10 | Valley School District 262 / 2,757 |
| 68. | 3.10 | Post Falls School District 273 / 35,945 |
| 69. | 3.09 | Glenns Ferry Joint School District 192 / 2,951 |
| 70. | 3.07 | Bliss Joint School District 234 / 834 |
| 71. | 3.07 | Lakeland Joint School District 272 / 26,800 |
| 72. | 3.07 | Soda Springs Joint School District 150 / 4,345 |
| 73. | 3.07 | Prairie Elementary School District 191 / 52 |
| 74. | 3.03 | Lewiston Independent School District 340 / 33,941 |
| 75. | 3.02 | Pleasant Valley Elementary School District 364 / 137 |
| 76. | 3.02 | Boise City Independent School District 1 / 189,540 |
| 77. | 3.02 | Grace Joint School District 148 / 2,011 |
| 78. | 3.02 | Genesee Joint School District 282 / 1,618 |
| 79. | 3.01 | Challis Joint School District 181 / 3,030 |
| 80. | 3.01 | Cottonwood Joint School District 242 / 2,708 |
| 81. | 2.98 | Nezperce Joint School District 302 / 868 |
| 82. | 2.97 | Plummer-Worley Joint School District 44 / 3,706 |
| 83. | 2.96 | Troy School District 287 / 2,001 |
| 84. | 2.95 | Coeur d'Alene School District 271 / 71,817 |
| 85. | 2.92 | Basin School District 72 / 3,391 |
| 86. | 2.92 | Moscow School District 281 / 27,334 |
| 87. | 2.91 | Kamiah Joint School District 304 / 3,535 |
| 88. | 2.91 | Mountain View School District 244 / 10,507 |
| 89. | 2.90 | Blaine County School District 61 / 21,323 |
| 90. | 2.88 | Clark County School District 161 / 780 |
| 91. | 2.88 | Mackay Joint School District 182 / 1,561 |
| 92. | 2.87 | St. Maries Joint School District 41 / 6,991 |
| 93. | 2.84 | Hagerman Joint School District 233 / 2,422 |
| 94. | 2.84 | Bear Lake County School District 33 / 5,903 |
| 95. | 2.82 | Potlatch School District 285 / 3,410 |
| 96. | 2.82 | Kendrick Joint School District 283 / 1,895 |
| 97. | 2.80 | Meadows Valley School District 11 / 1,302 |
| 98. | 2.79 | Whitepine Joint School District 288 / 1,802 |
| 99. | 2.78 | West Bonner County School District 83 / 11,603 |
| 100. | 2.78 | Lake Pend Oreille School District 84 / 29,046 |
| 101. | 2.75 | Swan Valley Elementary School District 92 / 558 |
| 102. | 2.74 | Kellogg Joint School District 391 / 8,187 |
| 103. | 2.72 | Garden Valley School District 71 / 1,727 |
| 104. | 2.70 | Salmon School District 291 / 6,972 |
| 105. | 2.65 | South Lemhi School District 292 / 787 |
| 106. | 2.65 | Council School District 13 / 2,210 |
| 107. | 2.64 | Wallace School District 393 / 4,589 |
| 108. | 2.62 | Orofino Joint School District 171 / 8,982 |
| 109. | 2.60 | Mullan School District 392 / 750 |
| 110. | 2.59 | Highland Joint School District 305 / 1,384 |
| 111. | 2.59 | Kootenai Joint School District 274 / 1,932 |
| 112. | 2.56 | Cambridge Joint School District 432 / 1,140 |
| 113. | 2.53 | Midvale School District 433 / 621 |
| 114. | 2.52 | Arbon Elementary School District 383 / 167 |
| 115. | 2.48 | Salmon River School District 243 / 1,250 |
Please note that we only rank locations with 'Average Family Size' data. The rank above might not be a complete list. Locations without 'Average Family Size' data are not listed.
*ACS stands for U.S. Census American Community Survey. According to the U.S. Census, if the date is a range, you can interpret the data as an average of the period of time.
