Tasks for Assessing Computational Thinking Skills at Secondary School Level

Abstract

Computer science has become an essential part of many disciplines. Skills of thinking computationally have become increasingly important for everyone. Systematic development of the skills of computational thinking (CT) includes developing the skills of solving problems by defining the problem, solving the problem algorithmically and analyzing the solution. As there has been a rise of teaching CT skills at secondary school level, an instrument for assessing CT skills is needed. The goal of this study is to modify and empirically test an instrument for assessing CT skills. An instrument with 10 tasks was created and a study was conducted with 649 secondary school students. Confirmatory factor analysis is used to confirm that the instrument is suitable for assessing skills of algorithmic design and pattern recognition. Results show that this modified instrument can be used to assess and set directions for developing CT skills at secondary school level.

Appendix A

Task 1. Crane operating

The crane in the port of Lodgedam has six different input commands:

left

right

up

down

grab

let go

Box A is in the left position; box B is in the position on the right.

Question:

Using the command buttons, swap the position of the two boxes.

Task 2. Popularity

Seven beavers are in an online social network called Instadam.

Instadam only allows them to see the photos on their own and their friends’ pages.

In this diagram, if two beavers are friends they are joined by a line.

After the summer holidays everybody posts a picture of themselves on all of their friends’ pages.

Question:

Which beavers’ picture will be seen the most?

Ari, Bob, Chio, Dmitri, Ehab, Fritz or Gerald

Task 3. Word Chains

For his homework, Thomas had to write words on cards and connect them with rubber bands.

The teacher told him to connect any two words that differ by exactly one letter.

Thomas did this, as you can see in the picture on the right.

When Thomas returned from having a break he got a surprise.

Peter, his little brother, had erased all the words!

Also, the cards were completely mixed up, as you can see in the image on the left.

Importantly, the rubber bands still connected them as before.

Thomas was sure he could put the words back in the correct place.

Question:

Which of the pictures below contains the words in exactly the right places?

Task 4. Geocaching

Two friends, Anna and Bob, are searching for treasure.

They have a smartphone app that shows them the direction to the treasure they are looking for.

The two boxes on the map show where the treasure is.

Anna is searching for box 1. Bob is looking for box 2.

Anna and Bob are standing in the same place. The picture shows the map and a screenshot of the smartphones.

Question:

Where are Anna and Bob standing?

Task 5. Irrigation System

The beavers have created a clever irrigation system for their fields. The water flows from a lake at the top of the hill all the way down to the fields numbered 1 to 6 at the bottom.

Along the water canals, the beavers have installed four water gates A, B, C and D, where the water can only flow either to the left or to the right.

Answer and Explanation:

Question:

Which water gates should be changed, so that only the fields numbered 2, 4, 5 und 6 are irrigated?

Task 6. Beaver Lunch

Hm, what to take for lunch today?

The cafeteria gives instructions on how to choose a Beaver lunch.

This is shown as a diagram:

Below the tray you see different types of food containers.

The numbers indicate how many containers of this type can be added to a tray.

Each container can only have food items put in it that are shown below it.

The numbers indicate how many food items of this type can be added to the containers.

Question:

Which of the following lunches is not a proper Beaver lunch?

Task 7. Button Game

You can play this game on the ground. Draw a board and put the colored buttons. One step means to move one button to top, down, right or left through one box.

Question

What is the least number of steps to put all green squared buttons into one line at the bottom of the board?

Task 8. Decorating Chocolate

Everything is automated in a chocolate factory: the sweets are sliding on a conveyer, and there is a robot with a syringe, which draws different shapes.

The robot can perform these commands:

• 1. Leaf – draws:

• 2. Circle – draws :

• 3. Rotate k – rotates the sweet clockwise by k°.

• 4. Repeat n

The robot will draw the flower as following:

Question

Which of the following command sequences the robot does NOT draw the flower?

Task 9. Pencils’ Alignment

A little beaver is bored of drawing and wants to play with a box of pencils.

• Pencils are taken from the box one by one from left to right.

• Pencils are placed in Mom’s and Dad’s boxes, also from left to right.

• The first pencil is placed in Mom’s box.

• Each other pencil is compared with the last pencil placed in Mom’s box. If it is not longer than the last pencil placed in Mom’s box, then it is also placed in Mom’s box. Otherwise, it is placed to Dad’s box.

Mom’s box after first pencil is placed, Dad’s box after first pencil is placed

Question

What will Dad’s box look like after the little beaver places the last pencil?

Task 10. Building a Chip

A small chip is composed of a grid of contacts (marked as dots). Some are already connected (marked as line segments). Connectors are always only between adjacent contacts, horizontally or vertically. We want to connect S and R with a continuous sequence of connectors, which do not touch any already connected contacts.

Question?

How many different ways are there to connect S and R with the least possible number of connectors?