Illustrative Mathematics
Equivalent fractions approach to non-repeating decimals
Trying to get your class to think of decimals as fractions and vice versa can lead to interesting discussions. After all, we can usually understand quickly that 1/4 is .25 but why is 1/7 not so easy to convert? This activity looks...
Scholastic
Scholastic: Max's Math Adventures: A Sweet Story
In this Max's Math Adventure, estimate pieces of candy with Max, Ruthie, and Pop. Features include a teacher's guide, activity sheet, and extra challenges.
AAA Math
Aaa Math: Estimating a Sum by Rounding
Use rounding to estimate the answer to an addition problem in this online game. As you play the game, running totals of correct and incorrect answers and your score are displayed.