Instructional Video
Khan Academy

Khan Academy: Bonus Video Origin of the Mutant Plural

9th - 10th
Why does 'goose' become 'geese' and 'foot' become 'feet'? David the Grammarian and Jake the Linguist explain.
Instructional Video
Sophia Learning

Sophia: Measuring an Irregular Distance: Lesson 4

4th - 6th
In this lesson, students learn how to measure a distance which is not a straight line (but not necessarily curved). It is 4 of 9 in the series titled "Measuring An Irregular Distance."
Instructional Video
Sophia Learning

Sophia: Measuring an Irregular Distance: Lesson 8

4th - 6th
In this lesson, students learn how to measure a distance which is not a straight line (but not necessarily curved). It is 8 of 9 in the series titled "Measuring An Irregular Distance."