It's good so far! Despite being a fraction of the planned final product, it seems to have a lot of detail and care in the lessons, and starts from a really easy level so absolute beginners to both art and pixel art can learn a lot.

Some things I loved:
1: The whole idea of making sprites for little mini games and seeing them in action.
2: How slowly and thoroughly each concept is taught.
3: The SFX and music.
4: The face it has a whole extra section for general art skills but in a pixel art context. It's really helpful to walk through the same knowledge for drawing through the lens of pixel art.

Suggestions I think would make it 1,000 times better, in order of how much I want them to happen:
1: MOD SUPPORT. I'm new to development, so I have no idea how hard it would be to add this, but modding always breathes so much life into games, and communities. Even with basic tools, I'm sure we would be flooded with fan-made lessons and mini-games to add sprites too, As well as QOL improvements and bug fixes. Most will not meet the quality standard but the sheer volume should make up for it.
2: MOD SUPPORT. please mr retro (if that even is your real name)
3: Set ways to practice each concept on your own after the more color by number sections. I get that those are the best way to teach properly with no teacher there, but I sometimes find myself focusing more on which pixels I need to add and erase then why I am actually doing so. I found it best to do a lesson, really pay attention, then switch over to Aseprite with my own reference image to practice it. I think it would do wonders to, for instance, after one of the shape classes, give you one last reference image without any guide dots, and a reminder of the basic steps "block out the basic shapes, clean up the outline, erase un-needed lines, refine shapes, add details" stuff like that without telling you exactly what to do. this is the kinda thing a mod could add easily, just sayin, ADD MOD SUPPORT.
4: This is a smaller just fun little thing I'd like to see, but it would be so cool if future challenges had you redraw the actual ui of the game! All the different coursers, the calculator thing, the wood grain background, even simple navigational arrows early on! you could learn about combining shapes and making good lines, them BAM, you can take the training wheels of for a second and put that into practice by making a new exit arrow!
5: Fix some bugs like the scroll wheel zoom being jank, and apparently the pinball section idk i have not reached it. And adding the ability to change keyboard shortcuts.
6: This might be unreasonable, but doing more with animations and tiles would be great. Especially if you could put it into practice. like an unfinished little rpg, and you need to make a tile set, a moving character, and some more detailed static enemy sprites.

ok, thanks for reading! I really did like it, if you got 12(13?) bucks lying around and want to learn the basics, this is a great place to do so, and will only get better, as the dev seems to actually actively be doing stuff, which is more then most early access titles get.

May I ask if you have a plan to update the Chinese version?