things you will need
The following items from the Discover Computing kit:
- 1 x Crumble
- 1 x Battery pack
- 2 x Red croc leads, 3 x Black croc leads, 1 x Green croc lead
- 1 x USB cable
A computer with a USB port and the Crumble software installed.
To make the egg detector holder, you will need:
- A4 card
- Craft scissors
- Double-sided sticky tape (or regular tape)
- Rubber bands
Connect the Crumble to power
Use one red croc lead and one black croc lead to connect the Crumble to the battery pack.
Add the Reed Switch
- Attach one red croc lead to a positive (+) connector on the battery pack and to any connector on the reed switch.
- Add one black croc lead to the remaining connector on the reed switch and the ‘A’ input/output connector on the Crumble.
Add the Buzzer
- Attach one black croc lead to a negative (-) motor connector on the Crumble and the negative (-) connector on the buzzer.
- Add one green croc lead to the remaining connector on the buzzer and the B input/output connector on the Crumble.
Connect the Crumble to a computer
Use the USB cable to connect your Crumble circuit to a computer with the Crumble software installed.
Code the detector
- Snap a ‘do forever’ loop to a program start block.
- Tell the Crumble to turn the buzzer ON if the reed switch is closed, otherwise leave the buzzer OFF
- Turn the battery pack ON.
- Send your code to the Crumble (using the green triangle) and test it out.
- Grab a magnet and place the magnet on the reed switch.
Assemble the egg detector
- Unplug the USB cable from the Crumble.
- Place the Crumble on the back of the battery pack, with the croc leads all pointing upwards.
- Take the buzzer and place on the front of the battery pack, with the croc leads all pointing upwards.
- Use a rubber band to secure in place.
Make the egg detector holder
- Turn the battery pack ON.
- Place the assembled egg detector next to one of the shorter sides of the A4 card.
- Roll the card around the assembled egg detector, leaving the reed switch outside of the card.
- Secure the sides in position with sticky tape.
- Fold and sticky tape the bottom of the card roll (the battery pack end).
- Fold the corners of the top end of the card roll inwards, leaving the reed switch outside of the roll and facing towards you.
- Secure the folds in place with sticky tape.
Decorate the egg detector
- Turn the egg detector so the back (the side without the red rectangle) of the reed switch is facing you.
- Cut shapes out (we used an egg shape) and attach to the end of your egg detector – so the switch is hidden.
- Get creative and decorate the rest of the egg detector holder.
Set-up the egg hunt
- Check once more that your egg detector is working. Place a magnet against the reed switch. If the buzzer sounds, then you are good to go!
- Tape small magnets inside some (not all) of the plastic eggs.
- Add chocolate eggs to those eggs with a magnet inside.
- Hide the eggs and take it in turn to find the eggs with chocolate inside using your new egg detector!