My 'Downloadable Articles' Homepage at http://dynamicmathematicslearning.com/homepage4.html has been updated with the following new items: 1) "What is the function?" Models the height of water being poured into a tilted container in a video clip with a simple differential equation to find the function. 2) "Relations between the sides and diagonals of a set of hexagons" Explores the analogous case for parallelo-hexagons of the parallelogram theorem that the sum of the squares of the sides of a parallelogram is equal to the sum of the squares of its diagonals. 3) June '13 Math e-Newsletter with info about new books, website, conferences, etc. At: http://frink.machighway.com/~dynamicm/newsletter.html 4) mathematical/mathematics education quote 5) mathematics/science cartoon.
My 'Dynamic Geometry Sketches' site available at: http://dynamicmathematicslearning.com/JavaGSPLinks.htm has been updated with the following: 1) A generalization of a parallelogram theorem to parallelo-hexagons, and Douglas?ï theorem for polygons. (New) 2) Hierarchical Quadrilateral Tree. (Updated) 3) Van Aubel's theorem and some generalization. (Updated) 4) Some unproved conjectures. (Updated)