Math concepts: Fraction/decimal multiplication, area model of multiplication Materials: Paper and pencil Tags: 5.NBT.B.7, 5.NF.4, 5.NF.6, I love the question at the heart of this lesson—it’s simple but counter intuitive. This is a perfect way to let kids look for something without The Launch Consider a rectangle. If the side lengths are whole numbers, then so is the area. Do …

## What’s the biggest rectangle?

Math concepts: Area, perimeter, number patterns Materials: Graph paper, pencil Tags: 3.MD.7.a-b, 4.OA2, 4.OA.3, 4.OA.5, 4.OA.5, 5.OA.3, MP1, MP2, MP3, MP5, MP6, MP7. Of all the rectangles with a given perimeter, which one has the largest area? This simple question launches a fascinating exploration. The Launch Remind students of the definition of area and perimeter. Then pose the following question: …