I bought these because I needed index cards of different colors for exercises in a workbook. I love the bright colors and the ruling on the one side helps keep my writing organized. The neon colors are high contrast for writing with ink pens (but I think pencil would work just as well). The best thing is that the pack is huge. I have more than enough to work with for this particular activity so these are going to last me a while. It's a good value but it also feels like a splurge in these colors.
I go through tons of 3x5's weekly and needed a way to buy enough that I wouldn't run out. These are perfect I only need to buy 3 of these packs and I have all I need for the summer!