To find out how many eighth graders took the survey, we can look at the data presented in the table. The table indicates that:
- 8th Grade Pizza: 54
- 8th Grade Tacos: 81
To find the total number of 8th graders surveyed, we add the number of students who preferred pizza to the number of students who preferred tacos:
\[ 54 \text{ (pizza)} + 81 \text{ (tacos)} = 135 \]
Therefore, the number of eighth graders who took the survey is 135.