The following is a summary of GCS 2016 standardized testing results from IOWA testing.
| Grade | English/ Language Arts | Math Total | Core | Social Studies | Science | Total |
| 3.6 | 4.8 | 4.0 | 4.3 | 4.1 | 4.2 | 4.2 |
| 4.6 | 5.5 | 4.7 | 5.0 | 5.6 | 6.4 | 5.4 |
| 5.6 | 6.2 | 5.6 | 5.8 | 6.3 | 6.1 | 5.9 |
| 6.6 | 9.4 | 8.3 | 8.9 | 9.3 | 9.1 | 9.6 |
| 7.6 | 9.0 | 10.7 | 9.7 | 9.4 | 9.1 | 9.6 |
| 8.6 | 11.4 | 12.6 | 12.4 | 11.4 | 10.9 | 12.2 |
Core= English/Language Arts and Math average
Total=Average of all test scores
The table shows that our 8th graders are performing at a high school level. The average 8th grader in their six month of the school year should be at a score of 8.6 to be at grade level. Any score above the grade level +.6 is trending above that grade level
Standardized test results for 2017-2018 year will be added when results become available.