I use this in my classroom as a daily starter which after the students become accustomed too shouldn't take more than 2 or 3 minutes.. It begins by introducing students to the basic concept of arrays and over time introduces them to prime & composite numbers, factors, multiples, prime factorization, perfect squares, Greatest Common Factor and Least Common Multiple. I got the idea for this at a LASaRD conference (Louisiana Autism Spectrum and Related Disorders) when in one of my sessions they talked about how autistic students need repetition and then slowly take away prompts. I figured why not use that with my students who were not autistic. Anyway, the idea is that students see the same concept everyday with only slight differences and over time information is pulled away so that students have to remember it. Being that it repeats every day for 100 days it has really helped my students to not only master concepts of factors, multiples and GCF/LCM, but it has helped to lock it in their long-term memory.
This is the pdf version of the Keynote presentation.
The Student Handout version is included.