# Featured

## Tallest Buildings in the World--Now, Design Your Own Mile High+ Tower

Last week, we used mathematics and engineering techniques to build the tallest tower out of index cards. The results were stagering: over 90% of Mathletes participated and built towers up to 103" in height.

## Index Card Tower CHALLENGE

After teaching the Mathletes how to measure the height of tall objects, or any object for that matter, including trees, buildings, etc., I wanted to challenge them to engineer their own tall structures.

## Clinometer: Finding the height of objects using Isosceles Right Triangles

A clinometer, also called a declinometer or an inclinometer, is an instrument that measures vertical slope, usually the angle between the ground or the observer and a tall object.

## New England Math League Contest (Grades 2-5)

After the children explored the logic questions of the Noetic Learning Math Competition, I had them attempt the New England Math League contest which is given to 4th gradeers and up. So Mathletes in 2-4th grade took the 4th grade test and 5th graders took the 5th grade test.

## Two-Digit Number that Certain Sum and Difference (K-1st Graders Only)

The K-1st Grade classes explored two-digit numbers that had a sum of a certain number and a difference of a certain number. This challenge causes them to think about addition and substraction at the same time and strategically look for patterns.