Havasuonline enrolls year-round for the current school year, students may enter at any time.
| 2008-2009 | |||
| AUGUST | 4 | Classes Begin | |
| SEPTEMBER | 1 | Labor Day | No School |
| OCTOBER | 6-10 | Fall Break | No School |
| NOVEMBER | 11 |
Veteran's Day | No School |
| 26-28 | Thanksgiving Break | No School | |
| DECEMBER | 18 | First Semester Ends | |
| 22-31 | Winter Break | No School | |
| JANUARY | 1-2 | Winter Break | No School |
| 5 | Second Semester Begins | In Session | |
| FEBRUARY | 16 | Presidents' Day | No School |
| 24 | AIMS High School Writing (Grade 10, plus any 11th & 12th grade students who have not yet passed) | ||
| 25 | AIMS High School Reading (Grade 10, plus any 11th & 12th grade students who have not yet passed) | ||
| MARCH | 16-20 | Spring Break | No School |
| 30 | TerraNova (Grade 9) testing window begins | ||
| APRIL | 1 | AIMS High School Mathematics (Grade 10, plus any 11th & 12th grade students who have not yet passed) | |
| 2 | AIMS High School Science (Grade 10 only) | ||
| 17 | TerraNova (Grade 9) testing window closes | ||
| MAY | 25 | Memorial Day | No School |
| JUNE | 19 | Classes End | |
| Note: Enrollment into the second half of the academic year is available through April. | |||
| 2009-2010 | |||
| JULY | 1 | Classes Begin | |
| SEPTEMBER | 7 | Labor Day | No School |
| OCTOBER | 5-9 | Fall Break | No School |
| 27 | AIMS High School Reading | ||
| 28 | AIMS High School Writing | ||
| 29 | AIMS High School Math | ||
| NOVEMBER | 11 |
Veteran's Day | No School |
| 25-27 | Thanksgiving Break | No School | |
| DECEMBER | 21-31 | Winter Break | No School |
| JANUARY | 1 | New Year's Day | No School |
| 18 | Martin Luther King Day | No School | |
| FEBRUARY | 15 | Presidents' Day | No School |
| 23 | AIMS High School Writing | ||
| 24 | AIMS High School Reading | ||
| MARCH | 15-19 | Spring Break | No School |
| APRIL | 7 | AIMS High School Math | |
| 8 | AIMS High School Science | ||
| MAY | 31 | Memorial Day | No School |
| JUNE | 18 | Classes End | |

