This first youtube video is about he difference between memorizing facts and knowing facts from memory. In my class I'm working on number sense and hoping that my second graders understand numbers and can be flexible with numbers. The second video gives a sense of how RekenReks help with number sense. Ten grid cards are similar to RekenReks to help with mental images that students use to make sense of numbers.
There IS a difference
Ignite Talk: the difference between learning basic facts "from memory" and memorizing them.
Intro to the Rek: Numbers are abstract, which is why many students have difficulty making sense of them. Incorporating a Rekenrek allows students to discover number and number relationships in a way that makes sense.