| Rank | Average Family Size ▼ | School District / Population |
| 1. | 4.34 | Dietrich School District 314 / 750 |
| 2. | 4.26 | Richfield School District 316 / 1,162 |
| 3. | 4.16 | Sugar-Salem Joint School District 322 / 5,157 |
| 4. | 4.07 | Cascade School District 422 / 2,923 |
| 5. | 3.93 | West Side Joint School District 202 / 2,521 |
| 6. | 3.81 | Wilder School District 133 / 2,911 |
| 7. | 3.80 | Shoshone Joint School District 312 / 2,953 |
| 8. | 3.78 | Snake River School District 52 / 8,013 |
| 9. | 3.76 | Marsing Joint School District 363 / 4,421 |
| 10. | 3.73 | McCall-Donnelly Joint School District 421 / 6,772 |
| 11. | 3.72 | Melba Joint School District 136 / 3,414 |
| 12. | 3.72 | Bonneville Joint School District 93 / 48,297 |
| 13. | 3.71 | West Jefferson School District 253 / 2,288 |
| 14. | 3.68 | Caldwell School District 132 / 33,356 |
| 15. | 3.68 | Aberdeen School District 58 / 3,630 |
| 16. | 3.67 | Jefferson County Joint School District 251 / 22,305 |
| 17. | 3.66 | Shelley Joint School District 60 / 9,350 |
| 18. | 3.65 | Cassia County Joint School District 151 / 23,023 |
| 19. | 3.65 | Murtaugh Joint School District 418 / 1,006 |
| 20. | 3.63 | Hansen School District 415 / 2,013 |
| 21. | 3.62 | Ririe Joint School District 252 / 2,693 |
| 22. | 3.62 | Homedale Joint School District 370 / 5,839 |
| 23. | 3.61 | Kimberly School District 414 / 6,710 |
| 24. | 3.60 | Vallivue School District 139 / 41,596 |
| 25. | 3.59 | Nampa School District 131 / 86,317 |
| 26. | 3.58 | American Falls Joint School District 381 / 7,076 |
| 27. | 3.57 | Notus School District 135 / 1,804 |
| 28. | 3.57 | Parma School District 137 / 5,468 |
| 29. | 3.54 | Three Creek Joint Elementary School District 416 / 72 |
| 30. | 3.53 | Blackfoot School District 55 / 21,546 |
| 31. | 3.52 | Teton County School District 401 / 10,212 |
| 32. | 3.51 | New Plymouth School District 372 / 5,072 |
| 33. | 3.51 | Middleton School District 134 / 16,127 |
| 34. | 3.51 | Madison School District 321 / 34,270 |
| 35. | 3.50 | Jerome Joint School District 261 / 19,462 |
| 36. | 3.50 | Weiser School District 431 / 8,591 |
| 37. | 3.50 | Lapwai School District 341 / 3,327 |
| 38. | 3.49 | Wendell School District 232 / 4,731 |
| 39. | 3.48 | Firth School District 59 / 4,016 |
| 40. | 3.48 | Preston Joint School District 201 / 10,114 |
| 41. | 3.47 | Rockland School District 382 / 557 |
| 42. | 3.47 | Kuna Joint School District 3 / 27,555 |
| 43. | 3.38 | Pocatello School District 25 / 77,277 |
| 44. | 3.38 | Clark County School District 161 / 823 |
| 45. | 3.37 | Gooding Joint School District 231 / 6,910 |
| 46. | 3.36 | Minidoka County Joint School District 331 / 20,681 |
| 47. | 3.35 | Butte County Joint School District 111 / 2,630 |
| 48. | 3.35 | Bruneau-Grand View Joint School District 365 / 2,380 |
| 49. | 3.35 | Castleford School District 417 / 1,458 |
| 50. | 3.34 | Fruitland School District 373 / 8,244 |
| 51. | 3.32 | Valley School District 262 / 3,038 |
| 52. | 3.31 | Idaho Falls School District 91 / 56,089 |
| 53. | 3.31 | Meridian Joint School District 2 / 194,641 |
| 54. | 3.27 | Camas County School District 121 / 1,156 |
| 55. | 3.25 | Marsh Valley Joint School District 21 / 6,110 |
| 56. | 3.25 | Grace Joint School District 148 / 2,271 |
| 57. | 3.25 | Mountain Home School District 193 / 23,778 |
| 58. | 3.24 | Filer School District 413 / 6,747 |
| 59. | 3.24 | Twin Falls School District 411 / 52,427 |
| 60. | 3.23 | Cottonwood Joint School District 242 / 2,743 |
| 61. | 3.22 | Boundary County School District 101 / 10,903 |
| 62. | 3.21 | Payette Joint School District 371 / 9,408 |
| 63. | 3.20 | Emmett Independent School District 221 / 16,732 |
| 64. | 3.18 | Troy School District 287 / 2,130 |
| 65. | 3.17 | Horseshoe Bend School District 73 / 1,585 |
| 66. | 3.16 | Lakeland Joint School District 272 / 26,689 |
| 67. | 3.13 | Buhl Joint School District 412 / 8,559 |
| 68. | 3.12 | Fremont County Joint School District 215 / 11,351 |
| 69. | 3.11 | Culdesac Joint School District 342 / 922 |
| 70. | 3.09 | Avery School District 394 / 537 |
| 71. | 3.08 | Genesee Joint School District 282 / 1,685 |
| 72. | 3.08 | Coeur d'Alene School District 271 / 74,669 |
| 73. | 3.07 | Boise City Independent School District 1 / 190,168 |
| 74. | 3.06 | Nezperce Joint School District 302 / 918 |
| 75. | 3.06 | Plummer-Worley Joint School District 44 / 3,905 |
| 76. | 3.04 | Oneida County School District 351 / 4,241 |
| 77. | 3.04 | Glenns Ferry Joint School District 192 / 2,368 |
| 78. | 3.04 | Kamiah Joint School District 304 / 3,858 |
| 79. | 3.03 | Council School District 13 / 2,195 |
| 80. | 3.02 | St. Maries Joint School District 41 / 6,744 |
| 81. | 3.02 | Moscow School District 281 / 27,847 |
| 82. | 3.01 | Post Falls School District 273 / 37,025 |
| 83. | 3.01 | Lewiston Independent School District 340 / 34,319 |
| 84. | 3.00 | Bliss Joint School District 234 / 924 |
| 85. | 3.00 | North Gem School District 149 / 778 |
| 86. | 2.98 | Bear Lake County School District 33 / 5,816 |
| 87. | 2.98 | Hagerman Joint School District 233 / 2,830 |
| 88. | 2.97 | Mountain View School District 244 / 10,197 |
| 89. | 2.95 | Prairie Elementary School District 191 / 73 |
| 90. | 2.94 | Garden Valley School District 71 / 1,795 |
| 91. | 2.93 | Soda Springs Joint School District 150 / 4,193 |
| 92. | 2.93 | West Bonner County School District 83 / 11,658 |
| 93. | 2.92 | Lake Pend Oreille School District 84 / 29,227 |
| 94. | 2.92 | Challis Joint School District 181 / 2,854 |
| 95. | 2.91 | Potlatch School District 285 / 3,477 |
| 96. | 2.89 | Whitepine Joint School District 288 / 1,670 |
| 97. | 2.83 | Mackay Joint School District 182 / 1,604 |
| 98. | 2.82 | Kendrick Joint School District 283 / 1,872 |
| 99. | 2.81 | Kellogg Joint School District 391 / 8,222 |
| 100. | 2.81 | Blaine County School District 61 / 21,269 |
| 101. | 2.80 | Basin School District 72 / 3,500 |
| 102. | 2.77 | Mullan School District 392 / 668 |
| 103. | 2.76 | Meadows Valley School District 11 / 1,221 |
| 104. | 2.75 | South Lemhi School District 292 / 690 |
| 105. | 2.72 | Kootenai Joint School District 274 / 1,814 |
| 106. | 2.71 | Swan Valley Elementary School District 92 / 619 |
| 107. | 2.68 | Salmon River School District 243 / 1,390 |
| 108. | 2.66 | Cambridge Joint School District 432 / 1,173 |
| 109. | 2.66 | Highland Joint School District 305 / 1,334 |
| 110. | 2.64 | Orofino Joint School District 171 / 8,859 |
| 111. | 2.63 | Wallace School District 393 / 4,302 |
| 112. | 2.59 | Salmon School District 291 / 7,068 |
| 113. | 2.52 | Pleasant Valley Elementary School District 364 / 76 |
| 114. | 2.39 | Midvale School District 433 / 530 |
| 115. | 2.32 | Arbon Elementary School District 383 / 180 |
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.
