Really nice drawings! -You might want to add a stronger sense of structure where the obliques insert to the illium. In the bottom left drawing, the muscle feels loose, like it's not attaching firmly to the illium. Being aware of the line of insertion could help. As it's squashed the muscle might spill over, but never looses its attachment. For even more solidity, you might want to make the form of the muslce, squash less like a water ballon, and more like a sandbag, or some firmer type of matter. I hope this helps :)

Looking good! I made a paintover with some corrections. - In some of them you've chopped it of at the top. Remember that it originates all the way up to the 5th rib. - It helps to memorize a curve running through all the origin points. Study the 3D model and note how this imaginary line runs from the 12th rib to the 5th. Later on, this will also help you place the serratus accurately since it interdigitates with the external oblique. Hope this helps :)

Great job with the gesture! The main issue I´m seeing is the way you place the origin. Something that helped me was to study the 3D model and analyze how the line connecting all the origin points wraps around the ribcage, then learn how to draw it from imagination, by trying the angle myself, then checking with the 3D model. I would also recommend drawing all digits, when praciticing anatomy. Hope this helps :)

Great first attempt! Did you go through and check your work against Proko's assignment answer videos? The beans look pretty accurate to me (the part copied from references), but your muscle groups are indistinct, a little bit off, and/or consisting of very few lines in several of the poses. It looks like you're just trying to figure out where everything goes, and there's nothing wrong with that, but try to check your work against the answer videos when you're done (and don't forget about the 3D model - which I totally did until just now). When I was doing the assignment, I tried to rough in where I thought the muscles went with a lighter pencil, and then I checked my work against the video thumbnails and corrected with a darker pencil. Hope this helps! Keep drawing and having fun :)