Quiz cards for kids.. clipped together at the top left? long and skinny.. what are they called?

I am looking to buy the cards that are quiz something or another and I cannot think of the name. I try too look on google but I am not specific enough. They are long and skinny and you're able to flip through them without them seperating from eachother. We used them when I was in elementary school. I saw them at the science museum but I don't want to spend 40 dollars there when I can buy them much cheaper online!