These links/sites allow you to print your own, some allow you to set the dimensions of the grid. Some include interesting options, like colour. Check them out. Try printing them with the lines in different colours, printing the grid over patterned paper (some of the plain-ish patterns will work well, but you might try a more heavily patterned paper just for fun) and printing a full cardstock sheet with a grid then punching out a shape to create a journaling block would be cool, as would printing on transparency sheets. And experiment with the grids for digital applications as well.
Incompetech has downloadable grids in a wide variety of designs, including overall dot patterns, a + grid, and other geometric grids. This page is a Plain Graph Paper PDF generator.
This link has a colour picker, so you can find the Hex number for a specific colour then create grid paper in that colour. I've added a download of a PDF as a sample - a celery green, basic grid PDF created using the link above.
Printfreegraphpaper lets you specify the type, paper size, and measuring units and creates a PDF.
Paperprintout.com has graph paper, but also templates for lots of other things - gift tags, todo lists, shopping lists, phone messages - many of which would be very useful as journaling blocks.
This graph paper generator lets you pick the grid colour, and make the axis bold or plain and downloads a PDF. It's a pretty simple one, but looks like US letter size paper only.
This Printable paper site has LOADS of interesting papers to print, including music paper and bowling score sheets, loads of dotty options, printable calendars, and some teacher resources (lesson plans, attendance, etc).
Free PDFs of cash receipts to download as PDFs with rent receipts, sales slips, donation receipts and more. Might be useful..
And because it sort of fits here, two new Address book templates - address book pages (Word format and as a PDF), and address book directory. This one which is a bit customizable. Might work for planner pages.
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