Quia! Mathematics Activities (Popularity: ): Educational activities for teaching mathematics including concentration, matching, flash cards, word search puzzles, and Java games. Interactive Mathematics Miscellany and Puzzles (Popularity: ): Java-based math resource including articles, puzzles and links. A+ Math (Popularity: ): Interactive math help for K-12 students with flashcards, Math Wordfind, Homework Helper and worksheets. Colorful Mathematics (Popularity: ): Educational software presents advanced mathematics to K-12 students in a game-oriented approach, using coloring and drawing techniques to illustrate concepts from graph theory and computer science. Pythabacus (Popularity: ): Description and instruction of using the ancient Pythagorean Abacus to do arithmetic. Mathschallenge.net (Popularity: ): A website dedicated to the puzzling world of mathematics and computer programming. Math Forum (Popularity: ): Resources, problems and forum for teachers and students in mathematics. Brain Teasers and Maths Puzzles (Popularity: ): Interactive logical and mathematical puzzles with feedback and detailed solutions. MatheMajik (Popularity: ): Indian site featuring calculation tricks and math puzzles. The Puzzling World of Barry R. Clarke (Popularity: ): Brain teasers, articles and puzzles forum.