7:56 AM, Tuesday March 22nd 2022
Your arrows are smooth & flowing through the space. You've also compressed & expanded them to show the depth, good wok. Your lineweight position is almost good, just make sure you're using them only for the overlapping part(where you did the hatching) to highlight the edge close to the viewer.
Other than few(especially the top left & bottom right), your leaves are following the flow line naturally. You can work on them a bit to make it look more natural. Use real leaves as reference if you can.
You've broken the silhouette in some of the leaves but in many of them you've cut back into already drawn part. It is recommended to do constructions using addtion & when you do add or remove stuff, think of whether it would be raised or lowered relatively.
One thing I would recommend is lowering the amount of contour lines drawl. Since we're not drawing exact copies of a reference, draw a contour for veins only if help convey the form more or doens't make the drawing more noisy.
Sometimes the ellipses here are not perpendicular to their minor axis(flow line of branch), see https://drawabox.com/lesson/1/5/minoraxis. Ghost multiple time before placing the mark for them as if not placed well they can break the drawing instantly.
The edges of these branches are straying a little but you've done them(along with forking) as instructed, these edges will get better with more practice.
Also you'll have easier time drawing these branches, if you place those ellipses near the extreme/sudden curves of flow line.
While you've done the required amount of pages, I think you repeated same plants(most of them are from demos) quite a lot. You could've used some variations.
Nice work on keeping the parts of plants enclosed within it's planned ellipse.
In some of the plants(like Pitcher plant) where you used branches, you've ignored the instruction of doing each edges separately, while it might seems easier that way it won't result in a smooth edge(since there are curves involved).
You've also broken the silhouette of the drawing to convey the forms of the plants.
You've drawn flow line for each petal & leaves and while some of them are stiff(like in flowers) & not natural(some in potato plants), you'll improve over time & with enough practice. Always spend good amount of time observing the flow in the reference before placing mark on the page.
While some mushroom are done well, I think some of them could use some stability, so they don't look as if they'll fall anytime, do minor axis for those construction before placing the ellipses.
In Cacti, I see that you've drawn the thorns all over the drawing. Don't do this, it can make drawing very noisy & hard to look at. When doing these details, you want to have a focal point, so viewer's eye can easily flow through the drawing, see the implicit detail section of lesson 2 https://drawabox.com/lesson/2/2/implicitexplicit.
Your plants construction are done as instructed. Please do those ellipses perpendicular to the minor or they would break the form you're constructing, do them in your warm ups & read the ellipses section from lesson 1 again if you can.
Congrats on completing lesson 3!
Feel free to start lesson 4.