For the actual art itself, which deserves its own category, see here: Witch Hat Atelier Awesome Art.
Specific manga chapters (and their corresponding anime episodes)
- Chapter 4 (Episode 3): Coco faces an obstacle that she's practically doomed to fail by Agott, sending her off to a testing location despite the fact that she had nothing more than a few days of understanding with magic. She takes what little magic she knows and combines it with the lifetime of experience working under her mother and handling cloth to make a hang glider with its own wind-power that carries her over to the top.
- Chapter 7 (Episode 5): Qifrey rescues his apprentices from a dragon by casting an even bigger dragon-shaped water spell (as seen in the picture). The scene appears briefly in the manga but the anime improves it to the point of making the spell much larger so the dragon looks like a gecko in front of it and transforming him into an Adaptational Badass.
- Chapter 9 (Episode 6): Qifrey stopping Olruggio from taking Coco to the Council of Magic Security. The spell is only a raised wall of water, but the possibility of facing Qifrey is enough to get Olruggio nervous.
- Chapter 11: Olruggio's "The Reason You Suck" Speech to Agott, calling the young girl out on only insisting on coming in order to show off instead of the original purpose: helping people during a flood.
- Chapter 12: The sister-apprentices showing up to save Agott and Coco from having memories erased.
- Chapter 17: Credit where it's due for Tartah. The moment Coco's fever spiked, he acted to cure her by working around his disability to identify medicines that, due to his colorblindness, he couldn't distinguish by color. First, he removed water from the liquid medicines, leaving behind the substances that were dissolved into them to narrow the medicine he needed down.
- And when he hits a roadblock when the narrowed down medicines look identical, he and Coco come up with a magic that can reconstruct the powders into looking like their original form so he can use his memory to identify them.
- Chapter 20: When the group runs across a puzzle that requires stepping on the proper tile in order to advance without failing their test, Agott uses water to check where the tiles are broken and they pool so that they know where to go.
- Chapter 29: It turns out that while the girls' collective knowledge couldn't actually turn Euini back to normal, they did restore his mind. The Brimcap himself is actually impressed.
- Richeh managed to create a Portal Door using the knowledge that gained from Euini and the others.
- Coco managed to steal the Magical Accessory that can allow Euini to regain his human form.
- Chapter 34: In order to pass their next test, all the girls work together to create an elaborate picturesque scene. An Parroting Pouch guides the sage and several children to a narrow entrance that expands and leads them down to a chamber, revealing a sight that none of the children who'd lived under the sea had seen before: rain and the sunlight from the skies above (via Gate Parasols) that form a rainbow. It works wonderfully.
- Chapter 43: Tartah finds Custas at the mercy of a gang of contraption thieves. As a child against a group of adult men, he has no chance in a fight, so he uses quick thinking to trick the men into believing he's calling a witch over, managing to scare them off and save Custas.
- Chapter 45: After struggling to come up with a way to help Custas, Coco and Tartah end up coming up with a brilliant solution: a combination of a cloak, walking crutches, and levitation magic known as a wingcloak that allows Custas not only mobility but the ability to fly. It not only involves an impressive bit of mechanical trickery for two young kids to figure out, but Coco has the great idea to hide the levitation spell in the inner lining of the cloak in order to not break the rules. After seeing him struggle through out the volume, witnessing Custas take to the skies alongside Coco and Tartah is nothing short of awe-inspiring.Just look... and see. Find the shape the problems and difficulties around you take. Stare at them head on, and you'll find endless ways to solve them. There's an answer waiting to be fashioned. Every time.
- Chapter 55: Depending how you feel about the Knights Moralis, Galga having his memories erased is either tragic or some well-deserved karma for the people who have been terrorizing Coco and her friends up until this point. The Knights Moralis are shown to play fast and loose with the memory spell on both the Brimhats AND their victims, so there is a bit of Catharsis Factor in Ininia wiping Galga's memory on a cruel whim.
- Chapter 63: Coco improvises a magical flamethrower to defend Estheath from the curtain leech mouths that were rushing his blind spot, having had only a moment to draw out a seal and aim it (all while being carried over Qifrey’s shoulder and flying through the air).