| Rank | Average Family Size ▼ | School District / Population |
| 1. | 5.15 | McLaughlin School District 15-2 / 2,541 |
| 2. | 5.12 | Smee School District 15-3 / 353 |
| 3. | 5.02 | Shannon County School District 65-1 / 13,437 |
| 4. | 4.70 | Todd County School District 66-1 / 9,575 |
| 5. | 4.24 | Dupree School District 64-2 / 1,980 |
| 6. | 4.23 | Eagle Butte School District 20-1 / 4,231 |
| 7. | 3.90 | Emery School District 30-2 / 952 |
| 8. | 3.70 | Leola School District 44-2 / 1,062 |
| 9. | 3.69 | Bennett County School District 03-1 / 3,441 |
| 10. | 3.66 | Wagner School District 11-4 / 3,891 |
| 11. | 3.65 | Andes Central School District 11-1 / 1,855 |
| 12. | 3.62 | Hanson School District 30-1 / 1,733 |
| 13. | 3.61 | McIntosh School District 15-1 / 941 |
| 14. | 3.60 | White River School District 47-1 / 1,644 |
| 15. | 3.59 | Estelline School District 28-2 / 1,963 |
| 16. | 3.56 | Castlewood School District 28-1 / 1,215 |
| 17. | 3.51 | Kadoka School District 35-2 / 3,257 |
| 18. | 3.51 | Willow Lake School District 12-3 / 958 |
| 19. | 3.51 | Sisseton School District 54-2 / 7,692 |
| 20. | 3.50 | Lyman School District 42-1 / 3,056 |
| 21. | 3.49 | Hamlin School District 28-3 / 3,274 |
| 22. | 3.48 | White Lake School District 01-3 / 827 |
| 23. | 3.45 | Avon School District 04-1 / 1,399 |
| 24. | 3.44 | Florence School District 14-1 / 1,040 |
| 25. | 3.43 | Faulkton School District 24-4 / 2,178 |
| 26. | 3.43 | Clark School District 12-2 / 2,706 |
| 27. | 3.39 | Oelrichs School District 23-3 / 466 |
| 28. | 3.37 | Timber Lake School District 20-3 / 1,881 |
| 29. | 3.35 | Montrose School District 43-2 / 1,202 |
| 30. | 3.34 | Grant-Deuel School District 25-3 / 1,059 |
| 31. | 3.29 | Newell School District 09-2 / 2,537 |
| 32. | 3.26 | Tea Area School District 41-5 / 4,985 |
| 33. | 3.26 | Brandon Valley School District 49-2 / 15,229 |
| 34. | 3.25 | Iroquois School District 02-3 / 1,162 |
| 35. | 3.25 | Chamberlain School District 07-1 / 6,192 |
| 36. | 3.25 | Tripp-Delmont School District 33-5 / 1,801 |
| 37. | 3.24 | West Central School District 49-7 / 6,109 |
| 38. | 3.24 | Garretson School District 49-4 / 2,723 |
| 39. | 3.24 | Colman-Egan School District 50-5 / 2,106 |
| 40. | 3.23 | Stanley County School District 57-1 / 2,896 |
| 41. | 3.23 | Warner School District 06-5 / 946 |
| 42. | 3.23 | Elkton School District 05-3 / 1,359 |
| 43. | 3.22 | Freeman School District 33-1 / 2,564 |
| 44. | 3.22 | Douglas School District 51-1 / 11,883 |
| 45. | 3.21 | Mount Vernon School District 17-3 / 996 |
| 46. | 3.17 | Highmore-Harrold School District 34-2 / 1,950 |
| 47. | 3.17 | Waubay School District 18-3 / 1,293 |
| 48. | 3.15 | Sanborn Central School District 55-5 / 1,185 |
| 49. | 3.14 | Groton Area School District 06-6 / 3,876 |
| 50. | 3.13 | Bridgewater School District 43-6 / 961 |
| 51. | 3.12 | Brookings School District 05-1 / 25,169 |
| 52. | 3.12 | Agar-Blunt-Onida School District 58-3 / 2,079 |
| 53. | 3.12 | Parkston School District 33-3 / 2,989 |
| 54. | 3.12 | Woonsocket School District 55-4 / 1,366 |
| 55. | 3.11 | Ethan School District 17-1 / 891 |
| 56. | 3.11 | Colome Consolidated School District 59-3 / 1,652 |
| 57. | 3.10 | Tri-Valley School District 49-6 / 4,690 |
| 58. | 3.10 | Summit School District 54-6 / 610 |
| 59. | 3.10 | Deubrook School District 05-6 / 1,925 |
| 60. | 3.10 | Greater Hoyt School District 61-4 / 261 |
| 61. | 3.09 | Britton-Hecla School District 45-4 / 3,142 |
| 62. | 3.09 | Hitchcock-Tulare School District 56-6 / 1,283 |
| 63. | 3.08 | Henry School District 14-2 / 544 |
| 64. | 3.08 | Bowdle School District 22-1 / 823 |
| 65. | 3.08 | Ipswich School District 22-6 / 2,265 |
| 66. | 3.07 | Sioux Falls School District 49-5 / 140,350 |
| 67. | 3.07 | Bison School District 52-1 / 970 |
| 68. | 3.07 | Vermillion School District 13-1 / 12,172 |
| 69. | 3.06 | Harrisburg School District 41-2 / 14,083 |
| 70. | 3.06 | Dakota Valley School District 61-8 / 5,854 |
| 71. | 3.06 | Aberdeen School District 06-1 / 30,413 |
| 72. | 3.06 | Stickney School District 01-2 / 576 |
| 73. | 3.04 | Edmunds Central School District 22-5 / 1,150 |
| 74. | 3.03 | Menno School District 33-2 / 1,557 |
| 75. | 3.02 | Belle Fourche School District 09-1 / 7,490 |
| 76. | 3.02 | Wall School District 51-5 / 1,788 |
| 77. | 3.02 | Flandreau School District 50-3 / 3,568 |
| 78. | 3.02 | Dell Rapids School District 49-3 / 5,050 |
| 79. | 3.02 | Gayville-Volin School District 63-1 / 1,164 |
| 80. | 3.01 | Sioux Valley School District 05-5 / 3,183 |
| 81. | 3.01 | Meade School District 46-1 / 18,163 |
| 82. | 3.01 | Centerville School District 60-1 / 1,716 |
| 83. | 3.00 | Elk Point-Jefferson School District 61-7 / 3,886 |
| 84. | 3.00 | Parker School District 60-4 / 2,062 |
| 85. | 2.99 | Canistota School District 43-1 / 1,045 |
| 86. | 2.98 | Watertown School District 14-4 / 24,445 |
| 87. | 2.98 | Waverly School District 14-5 / 1,108 |
| 88. | 2.98 | Wilmot School District 54-7 / 1,951 |
| 89. | 2.97 | Beresford School District 61-2 / 3,392 |
| 90. | 2.96 | Pierre School District 32-2 / 15,635 |
| 91. | 2.96 | Platte-Geddes School District 11-5 / 3,029 |
| 92. | 2.96 | Huron School District 02-2 / 14,661 |
| 93. | 2.96 | McCook Central School District 43-7 / 2,279 |
| 94. | 2.96 | Canton School District 41-1 / 5,377 |
| 95. | 2.96 | Baltic School District 49-1 / 1,884 |
| 96. | 2.96 | Lennox School District 41-4 / 5,734 |
| 97. | 2.96 | Irene-Wakonda School District 13-3 / 2,353 |
| 98. | 2.95 | Madison Central School District 39-2 / 8,557 |
| 99. | 2.94 | Rapid City School District 51-4 / 88,085 |
| 100. | 2.94 | Plankinton School District 01-1 / 1,276 |
| 101. | 2.94 | Eureka School District 44-1 / 1,543 |
| 102. | 2.93 | Big Stone City School District 25-1 / 725 |
| 103. | 2.93 | Mitchell School District 17-2 / 18,036 |
| 104. | 2.93 | New Underwood School District 51-3 / 1,453 |
| 105. | 2.92 | Redfield School District 56-4 / 3,664 |
| 106. | 2.92 | Bon Homme School District 04-2 / 4,770 |
| 107. | 2.91 | Deuel School District 19-4 / 3,139 |
| 108. | 2.89 | Rosholt School District 54-4 / 925 |
| 109. | 2.89 | Gettysburg School District 53-1 / 1,412 |
| 110. | 2.87 | Yankton School District 63-3 / 19,611 |
| 111. | 2.86 | Hoven School District 53-2 / 1,099 |
| 112. | 2.86 | Viborg School District 60-5 / 1,453 |
| 113. | 2.86 | Hurley School District 60-2 / 800 |
| 114. | 2.85 | Faith School District 46-2 / 689 |
| 115. | 2.85 | Doland School District 56-2 / 909 |
| 116. | 2.85 | Frederick Area School District 06-2 / 958 |
| 117. | 2.84 | Marion School District 60-3 / 1,455 |
| 118. | 2.84 | Langford School District 45-2 / 1,325 |
| 119. | 2.82 | Kimball School District 07-2 / 1,251 |
| 120. | 2.82 | Rutland School District 39-4 / 639 |
| 121. | 2.81 | Wolsey-Wessington School District 02-6 / 1,225 |
| 122. | 2.81 | South Central School District 26-5 / 899 |
| 123. | 2.81 | Wessington Springs School District 36-2 / 1,851 |
| 124. | 2.80 | Armour School District 21-1 / 1,002 |
| 125. | 2.79 | Northwestern Area School District 56-7 / 1,855 |
| 126. | 2.78 | Harding County School District 31-1 / 1,250 |
| 127. | 2.78 | Howard School District 48-3 / 2,350 |
| 128. | 2.78 | Jones County School District 37-3 / 1,064 |
| 129. | 2.78 | Corsica School District 21-2 / 1,240 |
| 130. | 2.77 | Lead-Deadwood School District 40-1 / 7,071 |
| 131. | 2.77 | Scotland School District 04-3 / 1,742 |
| 132. | 2.76 | Mobridge-Pollock School District 62-6 / 4,046 |
| 133. | 2.76 | Chester School District 39-1 / 1,590 |
| 134. | 2.74 | Alcester-Hudson School District 61-1 / 2,242 |
| 135. | 2.73 | Oldham-Ramona School District 39-5 / 847 |
| 136. | 2.72 | Spearfish School District 40-2 / 14,780 |
| 137. | 2.72 | Webster School District 18-4 / 2,744 |
| 138. | 2.71 | Elk Mountain School District 16-2 / 356 |
| 139. | 2.71 | Gregory School District 26-4 / 2,123 |
| 140. | 2.70 | Roslyn School District 18-2 / 748 |
| 141. | 2.70 | Lemmon School District 52-4 / 2,020 |
| 142. | 2.69 | Burke School District 26-2 / 1,329 |
| 143. | 2.68 | Milbank School District 25-4 / 5,391 |
| 144. | 2.68 | Herreid School District 10-1 / 540 |
| 145. | 2.68 | Custer School District 16-1 / 7,774 |
| 146. | 2.68 | Hot Springs School District 23-2 / 5,683 |
| 147. | 2.66 | Selby School District 62-5 / 1,858 |
| 148. | 2.64 | Lake Preston School District 38-3 / 1,165 |
| 149. | 2.64 | Arlington School District 38-1 / 1,851 |
| 150. | 2.63 | Winner School District 59-2 / 4,467 |
| 151. | 2.61 | Miller Area School District 29-4 / 2,958 |
| 152. | 2.60 | Haakon School District 27-1 / 1,632 |
| 153. | 2.59 | De Smet School District 38-2 / 1,730 |
| 154. | 2.59 | Edgemont School District 23-1 / 1,182 |
| 155. | 2.50 | Hill City School District 51-2 / 2,630 |
| 156. | 2.09 | Greater Scott School District 61-5 / 114 |
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.
