freshman this coming school year
...
Your class isn't abnormally short then. 5' 8" is taller than average for someone your age. Now, my brother is
tall - he was a freshman this year, and he's already 6', surpassing me by half an inch (I'm almost 18); that puts him in the 100th percentile for height in the US (meaning that if he was in a crowd of any 100 kids his age, he'd most likely be the tallest, with a few exceptions, of course).