Curated OER
Using Known Facts to Multiply and Divide Mentally
Building strong mental-math skills requires learners to have a strong number sense. They practice multiplying two and three-digit numbers in their heads using estimation or approximation. They estimate or round each number and then...
DataWorks
4th Grade Math: Multi-Step Word Problems
Solving word problems requires reading comprehension and math computation. Through an interactive slideshow presentation, fourth graders observe and follow each step toward solve multiplication and division word problems.
Teach Engineering
Show Me the Money
Class members learn how to estimate the total costs involved to design and build a bridge by including design, material, equipment, and labor costs. The activity includes a discussion about the trade-off between cost and aesthetics.