Disclaimer: Another little bit of a filler chapter but I had a lot of fun writing it so I hope you enjoy reading it. If you recognize it, I do not own it.

The welcome back to Hogwarts prank after the Christmas holidays was big and flashy. They charmed the teapots to shout Christmas tales and they used another spell that turned the meals to coal. A switching charm with piles of coal they had gathered and transfigured.

There were shouts of outrage but they just snickered and it switched back a few minutes later but it had been great fun to do. They had plenty of pranks planned but best to give the students a bit of time to settle in before setting them off. Give them a few moments to be at ease before they were set off.

As classes resumed, as did product testing and creation. They had made a tone of ideas over the holidays and now had the supplies to test and figure out how to make their ideas into reality.

Harry excitedly met the twins in the back room where they already had the cauldron set up. "So Fred, George what are we making today," Harry asked grinning to them. They had mentioned they had a great idea and he always loved to hear them.

The twins pulled out a package from Zonkos that they had clearly snuck out to buy, "this is glow in the dark gum, the gum glows in the dark. We were thinking we take the idea but alter it. How cool would it be to have the person glow in the dark, not the gum?"

His eyes widened, He no longer had any doubts at what magic could accomplish. He knew it was possible because he had seen the twins do the impossible since started. He loved the idea though. It had so many prank potential as well. "Bloody brilliant, got any ideas on how we can do it?"

"Always," the twins said together as they started taking apart the composition of the gum and altering it to fit their needs. Some of the information went over the first years head however, like always the twins were happy to explain and teach him as they went. Snape would have quite the laugh if he knew just how advanced Harry actually was in potions thanks to the twins.

It took a few hours for them to finally have a product they thought had the potential to work. Now it was testing time.

"Who's turn is it to test," George asked.

"Definitely yours my dear twin," Fred teased.

"No I do believe it is your turn brother dear," George corrected.

"Actually, I believe it is our dear Harry's turn," They finished together.

Harry laughed since it really was his turn to test the prank. Harry took the piece of gum, "Any potential side effects I should know about or look for?"

While they might be careless as they tested there potions on themselves, they were far from stupid and always knew the risks. "An itchy tongue."

"It may turn your lips green."

Harry laughed, "That's a strange side effect."

"The Coric root," George said. "Mixed with Morian seeds tends to turn teeth and lips green. We should have countered it but we haven't tested it fully so it may still pop up."

"Nothing too serious," Fred said. "Its a pretty safe concoction. Its made to be edible so nothing overly toxic."

"Overly," Harry laughed.

"Overly," They both agreed with a nod.

"Testone," Harry declared biting into it chewing, "Fruit flavors good... a bit too strong."

The twins nodded making note of the fact.

"Any tongue itching."

"Or twitching."

"Or uncomfortable sensations," They finished together.

Harry chewed for a moment longer. "No, its taste is a bit overpowering though. You might want to weaken that. It is too fruity."

They nodded again before turning off the lights. he did not glow but his mouth and tongue did. It was slowly spreading over his face some but stopped just before his nose. "Glowings too weak," George decided. It did make you glow just didn't spread far enough."

"A good start but we are not quite there," Fred agreed.

They quickly went back to the drawing board.

It took two weeks until they got the effect they wanted. Harry as he had been the original tester, got the opportunity to put it to use first. Harry grinned going to the dark astronomy tower for class chewing the gum. Everyone looked at him shocked as he entered. Glowing a bright eye-catching white. The glow was so bright it lit up the room slightly. He grinned seeing the expressions on their faces. it was exactly what he wanted it to be. This was definitely a success...and the flavor was much improved. "Do I have something on my face he mocked checking.

"No...your just a bit shiny is all," Neville offered to cause Harry to grin since the shy boy had started coming out of his shell. A few months before and he would never have dared say even that. "Did the twins prank you?"

Harry shook his head, "no, product testing."

Neville scrunched up his nose a bit, he couldn't imagine willingly consuming prank potions or products to test them out yet he was not overly surprised the trio of trouble makers did so. "Umm...was it a success?"

"Yep," he said chewing the gum.

The teacher looked at him shaking her head. Having a headache just knowing she truly did not want to know why her student was glowing. "Mr. Potter, may I ask why you are glowing in my class."

He gave her a bright mischievous grin. "Sorry professor. Prank production cannot be stopped."

"Why are you glowing."

"My gum."

She sighed tiredly. "Spit it out. We have class."

He did so but the glow did not go away. "Mr. Potter, why are you still glowing."

He covered up a laugh looking at her seriously. "Product testing. Apparently, the potion is potent."

The other students laughed as the teacher just got more irritated. "When will you stop glowing?"

Even if Harry wanted to, he could not possibly answer that as they had just tested the newest form of the product getting the full-body glow.

"Potentially...soon," he said with a shrug.

"Detention Mr. Potter. For testing potions on yourself and interrupting class time by glowing." She had never thought she would say those words after becoming a teacher.

"Sorry Professor," Harry lied as he took a seat beside Neville who was snickering behind his book. "So, want a piece of gum Neville?"

Neville laughed harder as did those near him and it took a few minutes before they managed to stop laughing. Even the Slytherins with whom they shared the class with got a good laugh over it. "No thanks Harry, I prefer not to glow."

"That's too bad. It is quite fun. And the gum is quite tasty."

"Mr. Potter. If I find my other students are glowing in the class, I know I have you to blame and you will be the one I assign detentions to," she promised warningly.

Harry wasn't bothered by it. Or the fact that the twins intended to test it the next day as well and would be going to her class while glowing. He also knew they would be convincing others to try it out as well seeing if the effects were universal so shed be getting a headache the next day as well.

It took about 24 hours for the effects to wear off showing they still had a bit of work to do. But it was a good prank otherwise. They just made it too strong. That is what tests were for after all.

The finished product did come in handy as they went to detention with Hagrid in the forbidden forest. They knew the dangers but a bright light, while making them noticeable, would be likely to scare away any dangerous creatures. It was a strange sight to see as the three glowing students trotted through the trees. Catching the eyes of the more sentient beings in the forest who just watched them not sure how to react.

Overall, it was an interesting new product.