| Rank | Average Family Size ▼ | School District / Population |
| 1. | 4.13 | Dietrich School District 314 / 816 |
| 2. | 3.83 | West Jefferson School District 253 / 2,274 |
| 3. | 3.76 | Sugar-Salem Joint School District 322 / 4,971 |
| 4. | 3.74 | West Side Joint School District 202 / 2,274 |
| 5. | 3.65 | Murtaugh Joint School District 418 / 1,031 |
| 6. | 3.60 | Aberdeen School District 58 / 3,702 |
| 7. | 3.57 | Jefferson County Joint School District 251 / 22,316 |
| 8. | 3.55 | Wendell School District 232 / 5,436 |
| 9. | 3.54 | Snake River School District 52 / 7,898 |
| 10. | 3.53 | Bonneville Joint School District 93 / 45,322 |
| 10. | 3.53 | Preston Joint School District 201 / 10,253 |
| 12. | 3.48 | Shoshone Joint School District 312 / 3,128 |
| 13. | 3.47 | Rockland School District 382 / 549 |
| 14. | 3.46 | Cassia County Joint School District 151 / 22,454 |
| 14. | 3.46 | Shelley Joint School District 60 / 9,417 |
| 16. | 3.44 | Kuna Joint School District 3 / 25,863 |
| 17. | 3.42 | Wilder School District 133 / 3,063 |
| 17. | 3.42 | Hansen School District 415 / 2,002 |
| 19. | 3.41 | Jerome Joint School District 261 / 19,389 |
| 19. | 3.41 | American Falls Joint School District 381 / 7,200 |
| 19. | 3.41 | Clark County School District 161 / 982 |
| 22. | 3.40 | Caldwell School District 132 / 34,538 |
| 22. | 3.40 | Vallivue School District 139 / 38,269 |
| 24. | 3.39 | Three Creek Joint Elementary School District 416 / 73 |
| 25. | 3.38 | Madison School District 321 / 33,461 |
| 25. | 3.38 | Blackfoot School District 55 / 21,668 |
| 25. | 3.38 | Firth School District 59 / 3,928 |
| 28. | 3.37 | Melba Joint School District 136 / 3,241 |
| 29. | 3.35 | Nampa School District 131 / 83,622 |
| 30. | 3.34 | Richfield School District 316 / 1,055 |
| 30. | 3.34 | Notus School District 135 / 1,701 |
| 30. | 3.34 | Ririe Joint School District 252 / 2,557 |
| 33. | 3.33 | Kimberly School District 414 / 6,232 |
| 33. | 3.33 | Bruneau-Grand View Joint School District 365 / 2,533 |
| 33. | 3.33 | Teton County School District 401 / 10,170 |
| 36. | 3.32 | Marsing Joint School District 363 / 4,351 |
| 37. | 3.30 | Homedale Joint School District 370 / 5,710 |
| 38. | 3.29 | Parma School District 137 / 5,163 |
| 38. | 3.29 | Middleton School District 134 / 15,084 |
| 40. | 3.28 | North Gem School District 149 / 822 |
| 40. | 3.28 | Fremont County Joint School District 215 / 12,140 |
| 40. | 3.28 | Valley School District 262 / 2,870 |
| 40. | 3.28 | Gooding Joint School District 231 / 6,805 |
| 44. | 3.27 | Minidoka County Joint School District 331 / 20,877 |
| 44. | 3.27 | Castleford School District 417 / 1,408 |
| 44. | 3.27 | New Plymouth School District 372 / 4,602 |
| 47. | 3.26 | Meridian Joint School District 2 / 184,676 |
| 48. | 3.25 | Fruitland School District 373 / 8,194 |
| 49. | 3.24 | Oneida County School District 351 / 4,240 |
| 50. | 3.23 | Grace Joint School District 148 / 2,249 |
| 51. | 3.21 | Marsh Valley Joint School District 21 / 6,824 |
| 52. | 3.20 | Bliss Joint School District 234 / 749 |
| 52. | 3.20 | Filer School District 413 / 6,845 |
| 54. | 3.18 | Idaho Falls School District 91 / 56,313 |
| 55. | 3.17 | Pocatello School District 25 / 76,013 |
| 56. | 3.13 | Plummer-Worley Joint School District 44 / 3,831 |
| 57. | 3.12 | Bear Lake County School District 33 / 5,835 |
| 57. | 3.12 | Twin Falls School District 411 / 51,059 |
| 59. | 3.11 | Butte County Joint School District 111 / 2,825 |
| 59. | 3.11 | Mountain Home School District 193 / 24,115 |
| 61. | 3.09 | Post Falls School District 273 / 36,257 |
| 61. | 3.09 | Lapwai School District 341 / 3,162 |
| 61. | 3.09 | Buhl Joint School District 412 / 8,666 |
| 64. | 3.08 | Payette Joint School District 371 / 9,962 |
| 64. | 3.08 | Horseshoe Bend School District 73 / 1,667 |
| 66. | 3.06 | Weiser School District 431 / 8,470 |
| 67. | 3.05 | Lakeland Joint School District 272 / 26,553 |
| 68. | 3.04 | Cottonwood Joint School District 242 / 2,675 |
| 68. | 3.04 | Nezperce Joint School District 302 / 940 |
| 70. | 3.03 | Glenns Ferry Joint School District 192 / 2,666 |
| 70. | 3.03 | Soda Springs Joint School District 150 / 4,338 |
| 72. | 3.01 | Emmett Independent School District 221 / 16,719 |
| 73. | 3.00 | Boundary County School District 101 / 10,972 |
| 74. | 2.99 | Blaine County School District 61 / 21,376 |
| 75. | 2.97 | Prairie Elementary School District 191 / 109 |
| 75. | 2.97 | Genesee Joint School District 282 / 1,716 |
| 77. | 2.94 | Hagerman Joint School District 233 / 2,433 |
| 78. | 2.93 | South Lemhi School District 292 / 625 |
| 79. | 2.92 | Coeur d'Alene School District 271 / 71,692 |
| 80. | 2.91 | Boise City Independent School District 1 / 184,995 |
| 80. | 2.91 | Troy School District 287 / 2,008 |
| 82. | 2.89 | Moscow School District 281 / 27,525 |
| 83. | 2.88 | Potlatch School District 285 / 3,281 |
| 84. | 2.87 | Whitepine Joint School District 288 / 1,669 |
| 84. | 2.87 | Lewiston Independent School District 340 / 34,136 |
| 86. | 2.85 | Kamiah Joint School District 304 / 3,927 |
| 87. | 2.84 | West Bonner County School District 83 / 11,433 |
| 88. | 2.82 | St. Maries Joint School District 41 / 6,788 |
| 88. | 2.82 | Lake Pend Oreille School District 84 / 29,408 |
| 88. | 2.82 | Kellogg Joint School District 391 / 8,365 |
| 91. | 2.78 | Mountain View School District 244 / 9,920 |
| 92. | 2.77 | Camas County School District 121 / 1,117 |
| 93. | 2.76 | Mackay Joint School District 182 / 1,487 |
| 94. | 2.75 | Midvale School District 433 / 664 |
| 94. | 2.75 | McCall-Donnelly Joint School District 421 / 7,552 |
| 94. | 2.75 | Basin School District 72 / 3,399 |
| 97. | 2.74 | Wallace School District 393 / 4,254 |
| 97. | 2.74 | Avery School District 394 / 340 |
| 97. | 2.74 | Highland Joint School District 305 / 1,475 |
| 100. | 2.73 | Mullan School District 392 / 770 |
| 100. | 2.73 | Challis Joint School District 181 / 3,104 |
| 102. | 2.72 | Meadows Valley School District 11 / 1,483 |
| 102. | 2.72 | Salmon School District 291 / 7,154 |
| 104. | 2.71 | Orofino Joint School District 171 / 8,993 |
| 105. | 2.70 | Council School District 13 / 2,025 |
| 106. | 2.67 | Culdesac Joint School District 342 / 883 |
| 107. | 2.65 | Garden Valley School District 71 / 1,961 |
| 108. | 2.64 | Kootenai Joint School District 274 / 1,730 |
| 109. | 2.63 | Arbon Elementary School District 383 / 139 |
| 110. | 2.62 | Cascade School District 422 / 2,410 |
| 111. | 2.61 | Kendrick Joint School District 283 / 1,739 |
| 112. | 2.59 | Pleasant Valley Elementary School District 364 / 98 |
| 113. | 2.57 | Swan Valley Elementary School District 92 / 758 |
| 114. | 2.55 | Cambridge Joint School District 432 / 1,147 |
| 115. | 2.54 | Salmon River School District 243 / 1,459 |
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.
