All Might, struggling slightly to stay in muscle form after his first battle and now this, sighed. He was going to have to handle the battle himself. He put some OFA power into his body and jumped up into the air right before the students jumped out. He quickly saw the two and fell back down with a boom.
Todoroki and Midoriya were quick to act, jumping out on opposite sides of All Might so that one would always be out of his sight. Todoroki launched ice attacks at the teacher, which were hastily smashed to pieces. Izuku observed All Might's movements, and eventually decided it was time to put his plan from the night before into action. The only issue was that he hadn't mentioned it to Todoroki yet, so he needed an easy way to get it across.
He jumped forwards at All Might, but was blocked at the last second. Luckily, the distracted All Might wasn't able to block the next wave of ice which slammed into his back. Izuku pulled his leg back and launched his other leg directly into All Might's stomach, pushing him back. Deku jumped over the teacher and mouthed two words to Todoroki, hoping it was enough. Fire. Big.
He was about to continue his assault on All Might, but the teacher moved first. He grabbed Deku's leg and threw him down on the ground, narrowly missing another hit as Deku rolled to the side. Deku threw himself onto his feet, feeling more power coursing through him. It was around then that he started to get suspicious, but he didn't have time to question it as he had to move to avoid another punch.
As soon as his feet touched the ground, he bounced into the air and shot off an air attack. As he hit the ground, he flew forward, hoping All Might would be unable to block both attacks. Unfortunately, All Might had 2 hands and a lot of muscle mass, easily holding off both attacks. He grabbed Deku's fist and spun, throwing him into a nearby building. Deku kicked backwards just before he hit the building, softening the impact. He jumped forward once more, this time even faster. He dodged a series of blows from All Might, dodging around, before landing a punch directly to the gut. He continued his assault, throwing the teacher back.
He was about to continue, but All Might reacted first. He ran forwards and punched Deku in the stomach with even more force than he'd previously been using. Even handicapped, he'd been holding back. He kicked Deku backwards, sending him flying into a building, bruised.
Deku felt more power surge into him. Once he recovered from his sudden shock and the attack, he analysed the situation. The more he felt his power increasing, the slower time seemed to move. He launched an air blast, sending a piece of rock flying up. With All Might's sight on him cut off for the moment, he ran forwards. He knew All Might would expect an indirect attack. Once he was just a few meters away, he sent a lighter air blast at the rock, causing it to fly forwards at All Might. Just as the teacher had finished smashing the rock, Deku was in front of him, delivering a series of punches.
Deku put 25% power into his fist, punching All Might in the stomach to send him flying one last time. Just as he stopped flying due to hitting a building, Todoroki finally launched a massive fire blast, blinding and further damaging the teacher. Before he was able to get up, the students managed to get the handcuffs on his wrist. He simply smiled and gave them a thumbs up.