1. **State the problem:** We need to find the current size of the graduating class at Arlington High School, given that it was 100 students a generation ago and is now 26% larger. 2. **Formula used:** To find the new size after a percentage increase, use: $$\text{New size} = \text{Original size} + \text{Percent increase} \times \text{Original size}$$ 3. **Convert the percentage to a decimal:** $$26\% = \frac{26}{100} = 0.26$$ 4. **Calculate the increase:** $$0.26 \times 100 = 26$$ 5. **Calculate the current size:** $$100 + 26 = 126$$ 6. **Answer:** The current size of the graduating class is **126 students**.