| Rank | Average Family Size ▼ | School District / Population |
| 1. | 4.49 | Wahluke School District / 8,342 |
| 2. | 4.20 | Mabton School District / 3,555 |
| 3. | 4.18 | Mount Adams School District / 4,380 |
| 4. | 4.10 | Granger School District / 5,751 |
| 5. | 4.06 | Toppenish School District / 14,415 |
| 6. | 4.00 | Othello School District / 14,916 |
| 7. | 3.98 | Wapato School District / 13,777 |
| 8. | 3.96 | Sunnyside School District / 24,342 |
| 9. | 3.86 | Royal School District / 6,437 |
| 10. | 3.85 | Bridgeport School District / 3,252 |
| 11. | 3.84 | Grandview School District / 14,998 |
| 12. | 3.82 | Taholah School District / 957 |
| 13. | 3.80 | North Franklin School District / 9,182 |
| 14. | 3.76 | Paterson School District / 451 |
| 15. | 3.68 | Nespelem School District / 1,354 |
| 16. | 3.67 | Pasco School District / 68,155 |
| 17. | 3.65 | Brewster School District / 4,566 |
| 18. | 3.64 | Warden School District / 4,022 |
| 18. | 3.64 | Quincy School District / 11,750 |
| 20. | 3.60 | Queets-Clearwater School District / 629 |
| 21. | 3.52 | Prosser School District / 12,996 |
| 22. | 3.47 | Prescott School District / 1,349 |
| 23. | 3.46 | Highland School District / 5,610 |
| 24. | 3.45 | Orondo School District / 1,651 |
| 25. | 3.42 | Roosevelt School District / 207 |
| 25. | 3.42 | Tukwila School District / 18,038 |
| 27. | 3.40 | Zillah School District / 5,123 |
| 27. | 3.40 | Yakima School District / 77,427 |
| 29. | 3.39 | Wellpinit School District / 1,116 |
| 30. | 3.36 | Battle Ground School District / 65,182 |
| 31. | 3.33 | Union Gap School District / 3,408 |
| 31. | 3.33 | Hockinson School District / 8,710 |
| 33. | 3.31 | Nooksack Valley School District / 10,056 |
| 34. | 3.28 | Summit Valley School District / 621 |
| 35. | 3.27 | Finley School District / 5,080 |
| 35. | 3.27 | Mount Vernon School District / 36,531 |
| 37. | 3.26 | Moses Lake School District / 39,664 |
| 37. | 3.26 | Lake Stevens School District / 39,977 |
| 37. | 3.26 | Kent School District / 158,233 |
| 40. | 3.25 | Federal Way School District / 130,706 |
| 40. | 3.25 | Carbonado School District / 856 |
| 42. | 3.24 | Camas School District / 28,306 |
| 43. | 3.23 | Monroe School District / 37,606 |
| 43. | 3.23 | Auburn School District / 84,053 |
| 43. | 3.23 | Palisades School District / 269 |
| 43. | 3.23 | Lynden School District / 18,386 |
| 47. | 3.22 | Kennewick School District / 85,577 |
| 47. | 3.22 | Bethel School District / 100,548 |
| 49. | 3.21 | Lind School District / 1,185 |
| 49. | 3.21 | Highline School District / 124,481 |
| 51. | 3.20 | Columbia School District / 3,892 |
| 51. | 3.20 | Kiona-Benton School District / 8,408 |
| 51. | 3.20 | Orting School District / 13,391 |
| 54. | 3.19 | Marysville School District / 69,169 |
| 55. | 3.18 | Tahoma School District / 37,376 |
| 55. | 3.18 | Ephrata School District / 11,632 |
| 57. | 3.17 | Evergreen School District (Clark) / 139,009 |
| 57. | 3.17 | La Center School District / 8,204 |
| 57. | 3.17 | Snohomish School District / 51,850 |
| 57. | 3.17 | Cashmere School District / 7,446 |
| 61. | 3.16 | Stehekin School District / 104 |
| 61. | 3.16 | Wenatchee School District / 42,698 |
| 61. | 3.16 | Sultan School District / 13,130 |
| 64. | 3.15 | Deer Park School District / 10,849 |
| 64. | 3.15 | White River School District / 22,116 |
| 66. | 3.14 | Renton School District / 115,511 |
| 66. | 3.14 | Manson School District / 3,583 |
| 66. | 3.14 | Mukilteo School District / 93,222 |
| 66. | 3.14 | Woodland School District / 11,971 |
| 66. | 3.14 | Mary Walker School District / 3,206 |
| 66. | 3.14 | Ferndale School District / 30,392 |
| 66. | 3.14 | Snoqualmie Valley School District / 35,054 |
| 66. | 3.14 | Green Mountain School District / 815 |
| 74. | 3.13 | Eastmont School District / 29,884 |
| 74. | 3.13 | East Valley School District (Yakima) / 15,549 |
| 74. | 3.13 | Dieringer School District / 8,802 |
| 74. | 3.13 | Arlington School District / 29,735 |
| 78. | 3.12 | Touchet School District / 1,124 |
| 78. | 3.12 | Granite Falls School District / 13,285 |
| 78. | 3.12 | Sumner School District / 43,512 |
| 78. | 3.12 | Issaquah School District / 98,660 |
| 82. | 3.11 | Medical Lake School District / 11,244 |
| 82. | 3.11 | Franklin Pierce School District / 50,424 |
| 82. | 3.11 | Ridgefield School District / 13,923 |
| 82. | 3.11 | Lakewood School District / 13,926 |
| 82. | 3.11 | Yelm Community Schools / 29,740 |
| 82. | 3.11 | Everett School District / 129,842 |
| 82. | 3.11 | North River School District / 223 |
| 82. | 3.11 | Puyallup School District / 118,946 |
| 82. | 3.11 | Riverview School District / 19,315 |
| 91. | 3.10 | Napavine School District / 4,316 |
| 91. | 3.10 | Orchard Prairie School District / 694 |
| 91. | 3.10 | Inchelium School District / 1,202 |
| 91. | 3.10 | Clover Park School District / 76,963 |
| 95. | 3.09 | Burlington-Edison School District / 20,952 |
| 95. | 3.09 | Mead School District / 50,919 |
| 95. | 3.09 | Davenport School District / 3,002 |
| 98. | 3.08 | Tacoma Public Schools / 208,938 |
| 98. | 3.08 | Adna School District / 3,736 |
| 98. | 3.08 | Selah School District / 18,675 |
| 101. | 3.07 | Keller School District / 503 |
| 101. | 3.07 | Northshore School District / 122,684 |
| 101. | 3.07 | Rochester School District / 14,285 |
| 101. | 3.07 | Elma School District / 8,932 |
| 105. | 3.06 | Reardan-Edwall School District / 4,260 |
| 105. | 3.06 | Fife Public Schools / 20,462 |
| 105. | 3.06 | Meridian School District / 9,779 |
| 105. | 3.06 | Eatonville School District / 12,084 |
| 105. | 3.06 | Valley School District / 1,413 |
| 110. | 3.05 | Star School District / 75 |
| 110. | 3.05 | Aberdeen School District / 20,368 |
| 110. | 3.05 | Walla Walla School District / 37,579 |
| 110. | 3.05 | Shelton School District / 23,747 |
| 114. | 3.04 | Kelso School District / 28,482 |
| 114. | 3.04 | Centralia School District / 22,909 |
| 114. | 3.04 | Mount Baker School District / 14,352 |
| 117. | 3.03 | Quillayute Valley School District / 6,709 |
| 117. | 3.03 | Raymond School District / 3,678 |
| 117. | 3.03 | Central Kitsap School District / 68,814 |
| 117. | 3.03 | Washougal School District / 19,168 |
| 117. | 3.03 | Edmonds School District / 154,583 |
| 117. | 3.03 | Central Valley School District / 76,487 |
| 123. | 3.02 | Richland School District / 62,323 |
| 123. | 3.02 | Vancouver Public Schools / 142,811 |
| 123. | 3.02 | East Valley School District (Spokane) / 25,817 |
| 123. | 3.02 | Cape Flattery School District / 3,197 |
| 127. | 3.01 | Steilacoom Historical School District / 20,920 |
| 127. | 3.01 | Conway School District / 3,102 |
| 127. | 3.01 | Mill A School District / 482 |
| 127. | 3.01 | Nine Mile Falls School District / 8,720 |
| 127. | 3.01 | Enumclaw School District / 25,179 |
| 127. | 3.01 | Winlock School District / 4,446 |
| 127. | 3.01 | Oakville School District / 2,363 |
| 127. | 3.01 | Lake Washington School District / 177,476 |
| 127. | 3.01 | Kittitas School District / 3,673 |
| 136. | 3.00 | South Kitsap School District / 68,017 |
| 136. | 3.00 | Sedro-Woolley School District / 26,212 |
| 136. | 3.00 | Chehalis School District / 14,527 |
| 136. | 3.00 | Hoquiam School District / 10,797 |
| 136. | 3.00 | Lake Chelan School District / 7,135 |
| 141. | 2.99 | Freeman School District / 4,305 |
| 141. | 2.99 | Evaline School District / 823 |
| 141. | 2.99 | West Valley School District / 28,648 |
| 141. | 2.99 | Riverside School District / 11,407 |
| 145. | 2.98 | North Thurston Public Schools / 94,104 |
| 145. | 2.98 | White Salmon Valley School District / 7,849 |
| 145. | 2.98 | Oak Harbor School District / 37,813 |
| 148. | 2.97 | Onalaska School District / 5,293 |
| 148. | 2.97 | Rainier School District / 5,062 |
| 148. | 2.97 | Toutle Lake School District / 3,348 |
| 148. | 2.97 | Lake Quinault School District / 1,187 |
| 148. | 2.97 | Omak School District / 10,481 |
| 148. | 2.97 | College Place School District / 12,899 |
| 148. | 2.97 | Bellevue School District / 124,003 |
| 148. | 2.97 | Entiat School District / 2,197 |
| 148. | 2.97 | Mercer Island School District / 22,699 |
| 157. | 2.96 | Tekoa School District / 943 |
| 157. | 2.96 | Satsop School District / 576 |
| 157. | 2.96 | Pe Ell School District / 1,737 |
| 160. | 2.95 | Longview Public Schools / 45,370 |
| 160. | 2.95 | Pateros School District / 1,542 |
| 160. | 2.95 | Klickitat School District / 592 |
| 160. | 2.95 | Shoreline School District / 65,547 |
| 160. | 2.95 | Spokane Public Schools / 221,110 |
| 165. | 2.94 | Waterville School District / 1,659 |
| 165. | 2.94 | West Valley School District / 18,872 |
| 165. | 2.94 | Great Northern School District / 695 |
| 165. | 2.94 | University Place School District / 28,944 |
| 165. | 2.94 | Naches Valley School District / 8,078 |
| 165. | 2.94 | Waitsburg School District / 1,555 |
| 171. | 2.93 | Southside School District / 2,227 |
| 171. | 2.93 | Ellensburg School District / 26,508 |
| 171. | 2.93 | North Kitsap School District / 45,966 |
| 171. | 2.93 | Cheney School District / 33,075 |
| 171. | 2.93 | Wishkah Valley School District / 835 |
| 171. | 2.93 | Okanogan School District / 5,637 |
| 177. | 2.92 | South Bend School District / 2,545 |
| 177. | 2.92 | Columbia School District / 1,172 |
| 177. | 2.92 | Liberty School District / 4,440 |
| 177. | 2.92 | Peninsula School District / 61,651 |
| 177. | 2.92 | McCleary School District / 3,015 |
| 182. | 2.91 | Colville School District / 11,571 |
| 182. | 2.91 | Stevenson-Carson School District / 6,199 |
| 182. | 2.91 | Toledo School District / 4,387 |
| 182. | 2.91 | Tenino School District / 9,479 |
| 182. | 2.91 | Kalama School District / 6,354 |
| 182. | 2.91 | Colton School District / 1,106 |
| 182. | 2.91 | Odessa School District / 1,509 |
| 189. | 2.90 | Cosmopolis School District / 2,013 |
| 189. | 2.90 | Almira School District / 489 |
| 189. | 2.90 | Boistfort School District / 894 |
| 189. | 2.90 | Stanwood-Camano School District / 32,907 |
| 189. | 2.90 | Darrington School District / 3,210 |
| 189. | 2.90 | Mary M. Knight School District / 1,428 |
| 195. | 2.89 | Tonasket School District / 6,638 |
| 195. | 2.89 | Bremerton School District / 44,966 |
| 195. | 2.89 | Tumwater School District / 36,566 |
| 195. | 2.89 | Damman School District / 769 |
| 199. | 2.88 | Oakesdale School District / 837 |
| 199. | 2.88 | Colfax School District / 3,985 |
| 199. | 2.88 | Bainbridge Island School District / 23,025 |
| 199. | 2.88 | Kahlotus School District / 384 |
| 199. | 2.88 | Soap Lake School District / 3,310 |
| 199. | 2.88 | Mossyrock School District / 3,994 |
| 199. | 2.88 | Lamont School District / 176 |
| 206. | 2.87 | Seattle School District / 609,471 |
| 206. | 2.87 | Centerville School District / 524 |
| 206. | 2.87 | Montesano School District / 8,042 |
| 206. | 2.87 | Pullman School District / 31,922 |
| 206. | 2.87 | Oroville School District / 4,439 |
| 206. | 2.87 | Olympia School District / 61,756 |
| 206. | 2.87 | Rosalia School District / 1,089 |
| 206. | 2.87 | Harrington School District / 739 |
| 206. | 2.87 | Bickleton School District / 366 |
| 206. | 2.87 | Castle Rock School District / 9,891 |
| 206. | 2.87 | Cascade School District / 9,560 |
| 217. | 2.86 | Willapa Valley School District / 2,231 |
| 217. | 2.86 | Mount Pleasant School District / 332 |
| 217. | 2.86 | Chewelah School District / 6,060 |
| 217. | 2.86 | North Mason School District / 14,752 |
| 221. | 2.85 | Cusick School District / 1,989 |
| 222. | 2.84 | Wishram School District / 394 |
| 223. | 2.83 | Sprague School District / 675 |
| 223. | 2.83 | Blaine School District / 15,974 |
| 223. | 2.83 | Newport School District / 8,083 |
| 223. | 2.83 | Clarkston School District / 18,461 |
| 227. | 2.82 | Thorp School District / 1,402 |
| 227. | 2.82 | Skamania School District / 789 |
| 227. | 2.82 | Asotin-Anatone School District / 3,245 |
| 227. | 2.82 | Bellingham School District / 102,121 |
| 231. | 2.81 | Curlew School District / 1,497 |
| 231. | 2.81 | Goldendale School District / 7,076 |
| 231. | 2.81 | St. John School District / 1,069 |
| 234. | 2.79 | Concrete School District / 4,840 |
| 234. | 2.79 | Dayton School District / 3,797 |
| 234. | 2.79 | Naselle-Grays River Valley School District / 2,240 |
| 234. | 2.79 | Palouse School District / 1,391 |
| 234. | 2.79 | Easton School District / 1,134 |
| 239. | 2.78 | Pomeroy School District / 2,191 |
| 239. | 2.78 | Trout Lake School District / 959 |
| 239. | 2.78 | Evergreen School District (Stevens) / 424 |
| 242. | 2.77 | Port Angeles School District / 30,152 |
| 242. | 2.77 | Vashon Island School District / 10,624 |
| 242. | 2.77 | Pioneer School District / 10,083 |
| 245. | 2.76 | Onion Creek School District / 398 |
| 246. | 2.75 | Crescent School District / 2,609 |
| 246. | 2.75 | Lyle School District / 2,809 |
| 246. | 2.75 | Wilbur School District / 1,342 |
| 246. | 2.75 | Orient School District / 879 |
| 250. | 2.74 | Dixie School District / 495 |
| 250. | 2.74 | Coulee-Hartline School District / 1,384 |
| 250. | 2.74 | Grand Coulee Dam School District / 4,236 |
| 250. | 2.74 | Ritzville School District / 2,388 |
| 250. | 2.74 | Selkirk School District / 2,213 |
| 255. | 2.73 | Kettle Falls School District / 5,385 |
| 255. | 2.73 | Griffin School District / 5,791 |
| 257. | 2.72 | Wilson Creek School District / 583 |
| 257. | 2.72 | Loon Lake School District / 1,710 |
| 257. | 2.72 | Morton School District / 2,742 |
| 260. | 2.71 | Wahkiakum School District / 3,148 |
| 260. | 2.71 | Endicott School District / 544 |
| 260. | 2.71 | Garfield School District / 789 |
| 260. | 2.71 | Anacortes School District / 20,332 |
| 260. | 2.71 | Northport School District / 1,482 |
| 265. | 2.70 | La Conner School District / 4,694 |
| 265. | 2.70 | Cle Elum-Roslyn School District / 7,379 |
| 265. | 2.70 | Steptoe School District / 281 |
| 265. | 2.70 | Glenwood School District / 457 |
| 269. | 2.69 | Ocosta School District / 7,559 |
| 270. | 2.68 | Shaw Island School District / 240 |
| 271. | 2.67 | Mansfield School District / 495 |
| 271. | 2.67 | LaCrosse School District / 680 |
| 273. | 2.65 | Quilcene School District / 1,760 |
| 274. | 2.64 | South Whidbey School District / 15,336 |
| 274. | 2.64 | Republic School District / 3,288 |
| 276. | 2.63 | White Pass School District / 4,080 |
| 276. | 2.63 | Hood Canal School District / 5,908 |
| 278. | 2.62 | San Juan Island School District / 7,662 |
| 279. | 2.61 | Coupeville School District / 9,696 |
| 280. | 2.60 | Index School District / 526 |
| 280. | 2.60 | Washtucna School District / 313 |
| 282. | 2.57 | Methow Valley School District / 5,230 |
| 282. | 2.57 | Grapeview School District / 2,567 |
| 284. | 2.56 | Port Townsend School District / 14,278 |
| 284. | 2.56 | North Beach School District / 7,329 |
| 284. | 2.56 | Chimacum School District / 11,350 |
| 287. | 2.55 | Skykomish School District / 627 |
| 287. | 2.55 | Sequim School District / 29,342 |
| 289. | 2.54 | Orcas Island School District / 5,387 |
| 290. | 2.52 | Ocean Beach School District / 10,032 |
| 291. | 2.46 | Creston School District / 1,151 |
| 291. | 2.46 | Brinnon School District / 1,250 |
| 293. | 2.44 | Lopez School District / 2,480 |
| 294. | 2.40 | Benge School District / 54 |
| 295. | 2.35 | Starbuck School District / 169 |
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.
