| Upper Perkiomen HS | 1,021 | regular | high |
| Upper Perkiomen MS | 672 | regular | middle |
| Upper Pittsgrove School | 340 | regular | other |
| Upper Pointe Coupee Elementary School | 241 | regular | other |
| Upper Providence El Sch | 435 | regular | elementary |
| Upper Saint Clair HS | 1,269 | regular | high |
| Upper Sandusky High School | 546 | regular | high |
| Upper Sandusky Middle School | 503 | regular | elementary |
| Upper School | 264 | regular | elementary |
| Upper Scioto Valley Elementary School | 257 | regular | elementary |
| Upper Scioto Valley High School | 159 | regular | high |
| Upper Scioto Valley Middle School | 54 | regular | middle |
| Upper Township Elementary School | 477 | regular | elementary |
| Upper Township Middle School | 419 | regular | middle |
| Upper Township Primary School | 460 | regular | other |
| Upper Valley Career Center | 988 | vocational | other |
| Upperman High School | 899 | regular | high |
| Upperman Middle School | 851 | regular | elementary |
| UPRIVER ELEMENTARY SCHOOL | 72 | regular | elementary |
| UPSALA ELEMENTARY | 181 | regular | other |
| UPSALA SECONDARY | 146 | regular | other |
| Upson-Lee Elementary School | 932 | regular | elementary |
| Upson-Lee High School | 1,177 | regular | high |
| Upson-Lee Middle School | 894 | regular | middle |
| Upson-Lee Primary School | 993 | regular | other |
| Upstream Learning Correspondence | 115 | regular | other |
| Upton Elementary | 574 | regular | elementary |
| Upton High School | 79 | regular | high |
| Upton Middle School | 690 | regular | middle |
| Upton Middle School | 206 | regular | middle |
| Uptown School Complex | 518 | regular | other |
| Upward Elementary | 389 | regular | other |
| Urban Academy | 416 | regular | other |
| URBAN ACADEMY LABORATORY HIGH SCHOOL | 128 | regular | high |
| Urban Academy of Greater Pittsburgh CS | 344 | regular | elementary |
| Urban ACT Academy | 298 | regular | elementary |
| URBAN ACTION ACADEMY | 178 | regular | high |
| URBAN ASSEMBLY ACADEMY FOR FUTURE LEADERS | 84 | regular | middle |
| URBAN ASSEMBLY ACADEMY OF GOVERNMENT AND LAW | 256 | regular | high |
| URBAN ASSEMBLY BRONX ACADEMY OF LETTERS (THE) | 413 | regular | other |
| URBAN ASSEMBLY CHARTER SCHOOL FOR COMPUTER SCIENCE | 488 | regular | high |
| URBAN ASSEMBLY GATEWAY SCHOOL FOR TECHNOLOGY | 407 | vocational | high |
| URBAN ASSEMBLY INSTITUTE OF MATH AND SCIENCE FOR YOUNG WOMEN | 352 | regular | other |
| URBAN ASSEMBLY MAKER ACADEMY | 535 | vocational | high |
| URBAN ASSEMBLY NEW YORK HARBOR SCHOOL | 518 | vocational | high |
| URBAN ASSEMBLY SCHOOL FOR APPLIED MATH AND SCIENCE (THE) | 530 | regular | other |
| URBAN ASSEMBLY SCHOOL FOR COLLABORATIVE HEALTHCARE (THE) | 377 | vocational | high |
| URBAN ASSEMBLY SCHOOL FOR EMERGENCY MANAGEMENT (THE) | 364 | vocational | high |
| URBAN ASSEMBLY SCHOOL FOR GLOBAL COMMERCE (THE) | 157 | vocational | high |
| URBAN ASSEMBLY SCHOOL FOR GREEN CAREERS (THE) | 326 | vocational | high |
