Arrows

They are pretty good, you start with your lines a bit wobbly, but they get better on the second page. Just as a reminder, remember you need to draw always confident lines, and to ghost them. You can also add superimposed lines to clarify overlaps between folds, and I wouldn't draw curved hatching lines, as they tend to flatten out the drawings, which is why it's better to stick with straight lines.

Organic forms

They're mostly good and confident, only issue I can catch, is that you aren't sticking to the simple form you should be aiming for on some of them, remember they need to be 2 identical balls connected by a tube with consistent width, so we can't have sausages that end up bigger in one side and smaller in the other.

Textures

In textures you've done a pretty good job, sticking to drawing cast shadows instead of just outlining forms, and wrapping them well around the forms of the dissections, as well as making good use of the silhouettes, only thing I can catch, is that on the gradients, you should have a "white bar" just like the black bar you have on your left, and you've drawn some stuff in there, try to keep track of that white bar, and aim to make the transitions towards white smoother.

Form intersections

Good job overall on the form intersections. You have some issues with the convergences, as you got divergences on some of your boxes. Remember not to rush them, and to put the same care to each box as you did on the box challenge.

The objective of this exercise is to draw forms on the same space with consistent foreshortening, to make them look like if they shared the same space. To do this, it's easier if you stick to shallow perspective on the boxes, so I recommend sticking to them on future attempts.

Organic intersections

I made some notes here, basically, remember you can add lineweight to clarify overlaps between forms, and try to be a bit bolder with your shadows, and just like in the sausage exercises, try to stick to simpler forms. It feels overall pretty solid though, good job!