Interactive apps

Teach, learn and practice computer science concepts.

No AI here, these apps are developed and maintained by humans!

Sample

Give it a try...

Tap/click a binary digit to toggle the bit to 0 or 1.
Show the carry bits.
When the answer is correct it will be highlighted in green.
Change the denary numbers to set your own problem.
Select Next Problem to try another random problem.
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Using the apps

Demonstrate a concept to students from the front of the class.
Students can practice using the same app.
Choose a question number or go random.
Monitor progress at a glance.
No installation required.
Runs client-side in browser. No log in and no advertisements.

Architecture apps

Little Man Computer

A better version than all the others for GCSE and A level.

Fully supports Cambridge OCR instruction set.

Little Man Computer
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Little RISC Computer

Fully supports AQA A level paper 2 instruction set.

Little RISC Computer
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Binary apps

Binary addition

Add two denary numbers using binary. Includes overflow and carry bits.

Binary addition
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Negative numbers

With sign and magnitude or two’s complement.

Negative numbers
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Binary subtraction

Subtract two denary numbers using binary.

Binary subtraction
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Fixed point numbers

Convert a denary number with a decimal component to fixed point binary or vice versa.

Fixed point numbers
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Floating point numbers

Convert a binary number with an 8-bit mantissa and 4-bit exponent into denary.

Floating point binary to denary
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Denary to floating point

Convert a denary number into a floating point number with an 8-bit mantissa and a 4-bit exponent.

Denary to floating point
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Normalisation

Normalise a binary number with an 8-bit mantissa and a 4-bit exponent, both stored in two’s complement.

Floating point normalisation
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Hexadecimal

Convert a denary number through binary to hexadecimal or vice versa.

Hexadecimal numbers
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Image apps

Image to bitmap

Show how an image is encoded into a bitmap.

Image to bitmap
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Bitmap to image

Show how a bitmap becomes an image.

Bitmap to image
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Programming apps

Trace table

Trace execution of Python, C#, OCR reference language or AQA pseudocode showing the values of variables and data structures.

Trace table
Start app

In the future...

The range of apps is increasing

More apps are being developed right now.

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Assessment

The apps are designed to be lightweight. There is no student or class data collection. If you are a teacher, we suggest you wander around the room as students are using an app and be aware of the data shown in the top right corner of the screen. For the binary apps:

The number of correct answers and the number of attempts is shown. E.g. 2/5 means two correct with five problems attempted.
If the user refreshes the page this counts as an attempt. This allows teachers to see at a glance who is refreshing the page frequently to get easier problems.
The counters reset when the session expires or after 24 hours.