I know Dr. Seuss, but not, if there is a specific blanket.
An ABC-blanket I can think of, though:
knit squares that you sew together in the end. (less wool / yarn to hold while knitting, too.) Knit them in different colors from one another.
There are 26 letters in the alphabet. If you want to do them all, that is a lot.
If you just want to do ABC you can make pattern / color blocks for the rest of your blanket or repeat them a few times.
To make a letter square: decide on the amount of stitches and rows (you need a swatch from yarn and needles used). Then take a piece of paper. Sketch your letter (alternative: search for a good font and print the letter).
Now take a checkered piece of paper and put it above, fill out the letter-squares on the paper with pencil/felt pen.
squares that are only partially covered by the letter are tricky. It takes some practice to find out which I fill out and which remain blank (that's why pencil is great).
Remember that you need side stitches (in the background color) and remember that a knit stitch rarely is square. Things will mostly be squashed a little. Maybe pay respect to that when sketching the letter.
Now you can start knitting with this color chart:
background color for all empty squares, letter color for all filled ones.
For that paw print pullover in my album I used a standart form from photoshop (paw print of course). Made it the desired size, put a line grid in Photoshop over it and filled the paw in a pale color. Then I printed that out and did the filling by hand (easier).
but that is my way of doing that.
In the PS-grid you can acutally pay very close respect to the shape of the stitches (long, tall or square)...
after knitting the squares together, knit or crochet a border around the whole thing to make it one single piece and more durable on the edges.
I will soon make a baby blanket out of this pattern:
I will use 9 squares only, to adjust the size. Since there are 4 pattern blocks and 2 ways to sew them in, I will make 8 pattern squares and one square with the babies initials (which I will not rely on until the day it is born (parents change names at rather odd cycles before birth). But the blanket can be mostly done before and will just get the finishing touches.