Draw four lines beginning and ending at the gray points to break this square into pieces that can be rearranged into five identical squares. Bonus: Suppose you can use any number of lines that begin ...
Students in Melissa Williams' kindergarten class at the Westminster School in Atlanta, Georgia, practice connecting quantities to written numbers — a key part of number sense. Credit: Holly Korbey for ...
Struggling with mental math? Students from class 6 to 10 now have a clever way to simplify tricky multiplication problems. The “doubling square” method turns large or complex calculations into quick, ...