We represent the Lollipop League

Thanks for bearing with us while we took the Easter break off – we return to you refreshed and full of chocolate.

The marvellous Spencer Organ, one of our Certified Educators, is a teacher at King Edward VI Sheldon Heath Academy (KESH Academy to its friends) in Birmingham. The school recently put on a student performance of The Wizard of Oz.


Spencer was in charge of performance technology, and wanted to see if he could fit a Raspberry Pi in as special effects equipment. The Tin Man’s heart presented a perfect opportunity. Spencer used the Pimoroni Unicorn HAT with a Model A+ to make the Tin Man’s heart (which was made out of red foil back when I did the same play as a kid) a glowing, animated thing of wonder. For more on HATs, see James’ post from last year.

(Spencer sensibly tweaked the brightness settings; a Unicorn HAT at full blast is positively retina-searing.)


The heart was programmed to pulse, giving the audience the impression it was beating.

Spencer says:

The code was relatively simple and I used a simple list to assign the x,y and colour data for each pixel to be used.


To give the effect of the heart beating and pulsating I gradually changed the brightness of the pixels from about 30 – 80%. It was important not to go too bright as I could have blinded the audience or other cast members!

while True:
    for bright in range (30,80):

This gave a very passable beating effect which looked stunning on the stage. The Pi was powered with a portable battery pack and to make backstage life easier the code was activated from boot using crontab with:

@reboot sudo python /home/pi/Pimoroni/heart.py &

Spencer has made the Python script you’ll need to make your own available on his website; check out the Raspberry Pi section of his blog for more teaching and learning ideas with the Pi. Thanks Spencer!


AndyD avatar

That is fantastic. I was one of the flying monkeys for my school’s performance of The Wizard of OZ. This appears to be a much more up market performance to ours, all those years ago (in the great southern land of OZ).

John avatar

This is such a great use of hardware! Really awesome!

Dogsbody avatar

guild… guild… we represent the lollipop GUILD!

*wanders off tutting to himself* :-p

Great use of a Pi though, well done :-)

Liz Upton avatar

Aargh – you’re right! I am confusing the Lollipop Guild with the Lullaby League. (Too late to change it now – permalinks and all that. It’ll be a lasting monument to my shame.)

ukscone avatar

Another one to add to the list. It’s getting quite long now. I might need to buy a new notebook soon :P

Liz Upton avatar

Oh, pthwap.

Jim Manley avatar

You filled up a terabyte drive on a notebook computer with Liz gaffs? Geez, I woulda thought a 16 GB tablet would have been big enough :D LOL, as in Lots of Love! We sexy sexagenarians are laughing with you, not at you … well, not in front of you, at least ;)

Gee 'The Rabid Inventor' avatar

That is such a nice use of the UnicornHat.

Mike Edwards avatar

Did the Lollipop Guild and the Lullaby League merge to become the Lollypop League.

Alan McC avatar

As Baldrick would say, (thanks to Spencer) “I have a cunning plan !

Great projet. Inspirational!

Comments are closed