Squishy CircuitsBridge Play School

What is a Electricity?• Our toys have lights, sounds, and

some even move

What makes toys work?• They have batteries, which give the

toys power

• What happens when batteries have no more power?

How does power move? • Anyone know who the power gets to

lights and makes sounds?– Wires! Which are a part of a circuit– A circuit like a road electricity moves on

Danger! Never touch wires

Lights in our house use power too!

• How do we turn on and off lights?– A Switch!

Open Circuit• When the power can be stopped, like

using a switch– When the switch off the light goes out

• Like a red light or stop sign on the street– When the switch on the light goes on

Closed Circuit• When the power always moves

– There is no switch– The light is always on

Making a Circuit• What do we need?

– Power Source• We will use batteries like our toys

– Light Bulb• We will use a little lamp

– Connection• We will use Play Doh!

Batteries• They have two sides

– Top and Bottom (positive and negative)– Connect each one to a side of the light

• We will use purple playdoh!• It conducts the electricity like a wire

Shorting out• What happens if the two playdoh

wires touch?– The light goes off

• The circuit is shorted out

Separating the connections

• To keep the two purple playdohconnections/roads from touching, we will use the white playdoh– It does not let the power move between

the purple ones• It’s inductive or insulates between the

purple ones

Creating our own circuit• Now you will use the playdoh,

batteries, and lights to make your own circuit

Here’s what you could make!

Let’s do it!• First one of you will make a circuit

– Then the other will? Or disconnect it?• Then make an animal or shape?

– Everyone make a shape or animal with the white dough

– Ask Miss Melissa, Miss Jessie, or Thomas’ Dad will help you add eyes, a mouth, then lights for the eyes!

Helping Hands• Ask for help to keep the power roads

separate– Remember the purple playdoh move the

power from the battery to the light– The white playdoh keeps the two purple

playdoh’s power separate

Backup Materials

Activities• Closed Circuit• Power Flow• Open Circuit• Short Circuit• Induction• Series Circuit• Parallel Circuit

Closed Circuit• Take two lumps of purple dough• Plug one wire from battery into each

piece of purple dough• Connect the two lumps with a light

• Does the light turn on?

Power Flow• Flip the light around so each leg is in

the opposite piece of purple dough– Does the light turn on?

• The power only moves in one direction

Open Circuit• Turn the light back around so power

goes the right way, the light turns on• Pull one leg out of the dough

– Does the light turn on?

• The road for the power is not connected– Like a bridge being opened

Short Circuit• Put the leg back in so the light is on• Push the two pieces of dough

together– Does the light stay on?

• The light went out, a short circuit– The two roads cannot touch

Induction• Separate the two pieces so the light

is on again– Make a sandwich with the white dough

between the two pieces of purple dough– Does the light turn on?

• The white dough is like a wall– It keeps the two purple doughs separate

• It is insulating

Series Circuit• Add another piece of purple dough

– Then add another light, like a train– What happens if you disconnect a light?

• Everything in the circuit is connected– Like cars on a train, if one gets loose

the others don’t go

Parallel Circuit• Now create three circles

– Purple on the inside, like a dot– While around the purple– Then another circle of purple

• Plug one end of the battery into each purple circle– Plug a light into each circle of purple– Pull out one of the lights– Do they all turn off?

Materials• Battery Pack (9V?)• Heavy-duty (9V?) snap connectors• 10mm LED assortment

Insulating Dough Recipie• http://youtube.com/Wz8rGNt-iEQ• 1-1/2 cups flour (1/2 cup?)• 1/2 cup sugar• 3 Tbsp vegetable oil• 1/2 cup distilled water• 1 tsp. granulated alum (optional)

Conductive Dough Recipie• 1 cup tap water• 1 1/2 cups flour• 1/4 cup salt• 3 Tbsp. cream of tartar• 1 Tbsp. vegetable oil• Food coloring (optional)

Safety• Never connect lights directly to the

batteries– Too much power can make them

overheat and pop• Safety glasses are recommended• The conductive dough can get hot

– Let it cool after disconnecting• Always experiment with an adult

– Never try this by yourself

Tips• Power only works in one direction

– Called polarity• Sometimes strands of insulating

dough still conduct and lights are dimly lit– Discuss resistance and capacitance

• Don’t cross the wires, it will short out the battery