3rd person
Almost 2 weeks had past since the entrance exams, and even though they passed they didn't stop training. Especially Frisk, as their 'quirk' was more suited for fights then physical activities.

Finally today was the day where they were going to UA. They all got changed, and Asgore gave another prep talk (though this one wasn't as good as the other one). Reluctantly, Sans used a shortcut to get them there. The only reason he was there was only because... well let's say Asgore can be really intimidating. They were teleported to the gate. Sans wished them luck and left.

After a minute of looking they finally found the door to class 1-A. And to say the least... it was massive. Even people with a gigantification quirk could fit.

They took their seats. Since the shortcut took 2 seconds, they were the first in the class. They just started to chat (except for Frisk because they rarely chat in public). Then the first person came through. It was the guy with blue hair from the hero exam. He walked up to Undyne. "Hello. My name in Tenya Iida, you may remember me from the hero course entrance exam."
Undyne thought for a moment before saying "Oh yeah you're that dude who interuppted Present Mic."
"About that, I wanted to apologise to you as I acted wrongly and out of turn. I see with your morals of justice, you will be a great hero someday." Iida apologised.
"No, its ok, I had already forgotten about it. And it already seems you changed so everything is fine, punk!!!" Undyne said with a smile. Iida thanked her and left to his seat. Iida just thought they called everyone punk and shrugged it off.

The next 2 people who came was a person with a bird head and a blond with spiky hair. The blond charged up to Undyne and Papyrus. "HOW THE HECK DID YOU TWO FREAKS GET MORE POINTS THAN ME IN THE ENTRANCE EXAMS!!!" The person shouted.
Then Papyrus spoke up. "Well its simple, he trained really hard, but I believe that you can do better than us if you just tried!" Papyrus said with a gleaming smile.
"DONT YOU DANG EXTRAS TAKE PITY ON ME!! I WILL BE THE NUMBER ONE HERO AND YOU WILL BE LUCKY OF YOU BE A SIDEKICK OF A D-RANKED HERO!" He shouted even louder than before.

Suddenly, a yellow caterpillar stood up. Oh wait, it was just a sleeping bag. "If you're here to make friends, leave now. It took you a whole 8 seconds to be quiet." The man Undyne now recognised as Eraserhead said. "Get changed, were going to have an quirk test..." he told the heros-in-training.

They all headed out then a brunette spoke up. "Wait, if we do this then we'll miss the opening ceremony."the brunette said. Then the erasure hero said in response
"Us here at UA arnt held by tradition so if I wanted i could expell all of you right now. You." He pointed to Undyne. "Before you got here how far could you throw a ball?"
"Around 164 meters." Undyne responded. "
"I mean without using you quirk." He said.
"Yeah 164 meters." Undyne said with a serious face. Everyone was in shock that she could throw a ball 164 meters with brute strength alone. Aizawa raised his eyebrow slights (what a big reaction) and said for her to use her quirk this time. Undyne summoned a spear beneath the ball as it was in the air propelling it forwards. Aizawa turned the machine to show the class and it showed 1.3Km. Everyone was shocked because this was just 1 spear, imagine 10. "This could be fun!" A person with pink skin said. "Is villain attacks fun? What about natural disasters? Is that fun? No, the world it cruel and if you think it is 'fun' it will strike you down. So how about the last person on the person with the lowest score gets expelled. Lets se if its 'fun' still." Aizawa said, leaving the class in shock.

(I'll just read out the top 3 people)
1. Papyrus
2. Undyne
3. Bakugo

"HOW DID YOU FREAKS GET MORE POINTS THEM ME!!" Bakugo shouted.
"Hard work, I guess" Undyne said with a straight face. Aizawa had to erase Bakugo's quirk before he could explode Undyne.
"Thats enough, you two." He said in a monotone voice. He pulled Bakugo closer with his scarf, "If you had gotten 1 point lower, I would of expelled you on the spot so keep it togethor or your dreams of being a hero will vanish." Bakugo was about to make a snappy comeback until he saw how intimidating Aizawa looked with his red eyes and kept quiet. He spoke again, but to the class this time. "Oh and the last person being expelled was just a logical deception. They get to stay." The kid with the green hair seemed so relieved. "Oh and since you finished the test early, you can have free period and get to know each other or whatever, just don't wake me up." Aizawa finished.

Undyne POV
After we all headed back to the classroom, Papyrus started introducing him and us to everyone. I just smirked and answered whatever questions they had while Frisk just sat there looking embarrassed. I just said Frisk doesn't like attention much and people pretty much left them after that.

A/N
Sorry for not updating in a while, I have been really demotivated and might go on haitus for a week. If that happens I'll tell you but ill see you later.