What is Reddit's opinion of Graph Paper Math Squared Notebook: Graph Paper For Kids Large 1/2 Inch Squares (Graph Paper Notebook 1/2 Inch Squares)?

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I bought this 1/2 inch squares Math notebook for my daughter a while back. The squares are pretty enormous, but are a good size for K-3 kids to put one number per square. It's pretty sturdy paper, at least 90gsm, I'd say.

This other one looks similar and came up in my recommendations as well.

Try adding "for kids" to your search and see if that gives you larger grids and wider spacing. Wide ruled is 7mm spacing, I believe... or you can search for "4 squares per inch" (which would be about 6.5mm squares).