{Modern AU}

The day could not have gone by slower. Kai was constantly looking back to the clock to see how close it was to 2:30pm. Not enough, as each minute seemed like an hour, and every hour seemed like a lifetime. He'd long stopped listening to the teacher when he felt a tap on his shoulder.

The brightest student in the class, Jinora Gyatso, had just gotten his attention, and was tilting her head over at their teacher, who promptly called his name.

Luckily, Jinora Gyatso also happened to be his best friend.

"Kai Fong!"

He whipped his head towards the front of the class, where his teacher was tapping his foot, looking impatiently at him. "Yes, Mr. Raiko?"

"I asked you what the answer to our review question was. About the holiday we all celebrate every summer?"

Kai's mind was drawing to a blank, when Jinora whispered, "Yangchen's Festival," into his ear.

"Yangchen's Festival," Kai repeated confidently.

"Correct," Mr. Raiko said, but he continued frowing. "Mr. Fong, would it hurt to pay attention for the last half hour? Spirits, kids," he said, shaking his head before directing his attention to the rest of the class, "you're going to be starting middle school in a few months. It's different than elementary school."

Kai zoned out again, looking at the clock. He'd heard this speech about a million times already and hadn't paid enough attention to get to the end of a single one of them. Still, he had to wonder, as he glanced over at Jinora, who was listening intently, if things really would be different. Kai would be going to the local public school while Jinora would be attending a small alternative school, which she'd applied for five months ago and (unsurprisingly) had bee accepted just over a month ago.

The entire class almost burst with relief and excitement when the bell rang to indicate that the day was over. Mr. Raiko had barely gotten in a "Happy Summer Vacation!" as the students filed out of the room, bubbling with news of their summer plans.

Picking out a short-haired head with a small bun on the side from the crowd, Kai caught up with Jinora, whose backpack always looked too big for her tiny body. She smiled over at him when she felt his presence.

"You coming home with me?" she asked with a wide grin. One of her teeth was missing (the tooth fairy had been very generous just two weeks ago), but her smile was still the prettiest thing Kai had ever seen. Aside from her eyes, maybe.

"Yup!" he said with an equally delighted him. "Summer fun buddies?"

"Summer fun buddies," she confirmed as they walked out of the building (for the last time, Kai realized). That stupid "middle school will be different" speech still nagged at the back of his head, but he shook it off when they climbed into the Gyatso family car. Jinora's little brother, Meelo, was (thankfully) sound asleep, and her mom hadn't picked up Ikki yet.

"Hey, Kai!" Mrs. Gyatso greeted. "Looking forward to summer vacation?"

Kai beamed at her. "Yep," he said, before they drove off.

They were eating s'mores and drinking root beer in Jinora's treehouse that night when their former teacher's speech began rattling in his mind again. He stared down his unfinished s'more while Jinora was going off about constellations and how much clearer they would be when they took their yearly trip to the family cabin when she noticed how silent he'd become.

"Kai?" she asked softly. "Is everything okay?"

"It's fine," he said, "I just keep thinking… Jinora, is everything going to be different?"

"What?" Jinora tilted her head questioningly at him.

"Like Mr. Raiko said. Well, what I payed attention to, anyway. We're going to different schools, and I'll have to experience all of those new things alone. What if…"

"What if one of us makes new friends and the other doesn't? What if we drift and we stop being best friends?" Jinora looked intently at Kai, whose eyes widened. It was like she'd read his mind. "I've worried about that, too. But that's why we said we would visit each other once every week once school starts again, and spend every birthday and holiday together." She took his hand in hers and squeezed it, smiling softly. "Best friends don't stop being best friends that easily, okay? I won't let it."

Kai smiled back at her. "Me neither."

"You know, I could also try to convince my parents to let you come with us on our trip so we could have more time together before school starts…"

"What? Jinora, that's your family's trip," Kai said, his eyes widening. "Besides, they'd have to talk to Mako and Bolin, and-"

"I want you to be a part of it!" Jinora insisted. "We're summer fun buddies."

Kai nodded. "Right."

She held up her bottle of root beer. "To a happy vacation?"

With a short laugh, Kai held his bottle up, clinking it against hers. "To a happy vacation."

As they gulped down their drinks (Kai always chugged his down to finish first), Kai felt the worry melt away, as he listened to her go on about constellations. Whatever the future had to bring, he knew that he could take it with his best friend, one day at a time.