Printable notebook paper come in handy when taking class notes or scribbling down a recipe that you just watched on the television. If someone gives you a telephone number or an address over a phone call, you can use the paper to note it down.
Free Printable Notebook Paper
All the printables come with black or colored horizontal lines with a margin on the left side. They would look appealing when filled with nice handwriting. However, since you are prone to use them when in a hurry, you need not care too much about your handwriting in those cases.
If you are taking down class notes or noting your observations in the lab, you can compile a set of such notebook paper templates in a file to keep everything organized and neat. Number the pages if you so wish.