**Summary:**

This lesson is about famous mathematician Karl Gauss, it combines to 2 parts: The mathematical problem as well as an inquiry part. The maths problem will enable students to investigate different ways to work out the sum of all numbers when added from 1 to 100. The second part requires students to investigate a bit about Karl Gauss’ life as well as his contributions to Maths.

# Australian Curriculum Links:

- Select and apply efficient mental and written strategies and appropriate digital technologies to solve problems involving all four operations with whole numbers (ACMNA123)
- Continue and create sequences involving whole numbers, fractions and decimals. Describe the rule used to create the sequence (ACMNA133)

**Lesson:**

Introduction:

1. Start off with a little story about Karl Gauss, (the story goes) “When a teacher asked him to add up the numbers between 1 and 100, (to keep him busy) Gauss quickly found a short cut for the answer in 3 minutes!”

Body:

7. Personally, I showed the video link below, which shows how Karl Gauss calculated it so quickly. This ties it up nicely and the kids will probably enjoy the accent in the video!

8. “Ticket out the door”- I often use this, where students write down how they solved the problem on paper which gives you another idea of how they worked it out.

**Assessment:**

- Using the worksheets, you can see how the students arrived at the answer as well as the strategies they used.
- Anecdotal Notes- These can be taken whilst watching the students complete the task.
- “ticket out the door”- I often use this

# Resources:

- Youtube video at http://www.youtube.com/watch?v=Prc7h8lyDXg
- Karl Gauss Investigation – attached worksheet