Selecting and Testing some paper stock for Cartoon sketching class

Reading through the excellent caricature drawing reference book Face Off by Harry Hamernik, I got reminded of the existence of ledger size (11" X 17") paper and the great value offered by regular office copy paper for drawing practice. Thus picked up this Hammermill Copy Plus 20 lb paper and some ledger size card stock at the local Staples for some doodle tests.
The Sharpie Fine Point glided smoothly and laid down crisp black strokes on this 20 lb paper.
Given the thinness of the sheets there was some light ink bleed through that stained the sheet below, but it remain still usable for doodle practice. It really makes sense to rely on a supply of inexpensive paper for the large amount of sketching papers required by large groups of students.
Pack of 125 sheet of 67 lb ledger size card stock.
The lower priced cover stock available online (left sample) is cream (or perhaps already showing some yellowing from lack of buffering). The acid-free labeled version (sample on the right) found in stores retails for almost double the price. Either one would be fine for initial sketches and earlier drawing practice, but as the students improve it would be best to switch to the acid free version to ensure the maximum longevity of the drawings.
The ledger size 67 lb Staples cover stock paper (11" X 17") folded in half can work well as an inexpensive portfolio cover to hold students sketches and drawings. It is fairly sturdy, and it can easily be decorated with a Sharpie pen illustration. The contents could be secured with a simple paper binding clip. Both paper products tested would make fine additions to the Cartoon Sketching Class selection of available supports.