When we originally posted, we published just two options for squared graph paper notebooks. One quad ruled, i.e. with quarter inch grid squares and the other with one centimeter grid squares.
Teal Graph Paper Notebook Quad Ruled (left)
Kids One Centimeter Grid Paper Notebook (right)

They were a huge hit and the quad ruled rapidly became a best-seller, topping the Amazon search results (sadly no longer - it's a shame because the design is so much more inspiring for kids than the quickly churned out boring graph notebooks that now top the Amazon charts). Anywho,
because they were so well liked, we did a set, all in different shades of blue, so that Math students could have a smart matching set, one for each Math topic.

We also put the more child friendly design from the One Centimeter Grid Paper Notebook on to a quad ruled notebook so that kids at middle school would have something that's right for them when progressing to the smaller squared grid. It's in green so it's easy to differentiate from the more advanced Math design.
Quad Ruled Graph Paper Notebookwith a
design for younger, middle-school kids
All are a good size (8.5" x 11" - that's virtually the same as A4) with paper thick enough to minimize ink bleed-through (55 lb), faint lines that don't overpower notation and unit conversion tables at the back.
We also now do aesthetic graph paper notebook designs under the Imprint 'Vintage Inspirations'. One is below, but i
f you'd like to see them all, it's best to head over to our USA Graph Paper Notebook page.