Month: December 2022

Do you know you can make a pH indicator with the red leaves from a poinsettia plant? Red poinsettia leaves contain anthocyanins which change colour in the presence of acids or alkalis.

Acids have a low pH ( below 7 ), and alkalis have a high pH ( over 7 ).

If it’s not the season for red poinsettia leaves, red cabbage also makes a brilliant pH indicator.

You’ll need

A handful of poinsettia leaves

Pan

Water

Scissors

Sieve

Beaker

Test tubes or small transparent containers

Substances to test – lemon juice, vinegar, baking soda in water, water

Coffee filter – optional

Instructions

Place about 200ml of water in a pan and heat gently.

Cut a handful of red poinsettia leaves with the scissors and drop them into the pan.

Bring the water and poinsettia leaf mixture to the boil and then leave to

These simple boat themed STEM challenges are easy, fun and great for all ages.

The challenges work brilliantly for older children who can use them to practise setting up an investigation correctly and can be simplified for younger children who might like a pirate or underwater theme!

Choose a challenge, design and build your boats and then start testing!

Older children can experiment with motors ( remember to cover the battery to keep it dry ). While younger children might find foil or recycled boats easier to make.

Boat STEM Challenge Investigation Ideas

These obviously depend on the type of boat you’ve made, but are a good starting point for any investigation.

Boat STEM Challenge 1

Does the boat float? Fill a container of water and test to see if the boats float. If they don’t float try adding corks or long balloons to the bottle or change the

This mini science investigation shows you how to make a DIY barometer to measure air pressure. Air pressure can be used to predict the weather and is one of many factors used by meteorologists.

What does low or high pressure mean for the weather?

Low pressure usually means wet, cloudy, rainy weather while high pressure is an indicator of dry and cool weather.

Barometers are used to measure atmospheric pressure.

What is atmospheric pressure?

The Earth has a layer of air surrounding it. This air has weight and presses down the Earth. At higher altitudes the air is thinner so air pressure is lower.

To make a barometer you will need

Jar or coffee can

Elastic band

Pin or cocktail stick

Tape

Glue

Straw

Paper

How to make a barometer

Blow up the balloon a little bit, the more air in the balloon, the greater

This simple salt lava lamp is a fun twist on the more traditional homemade lava lamp that uses a fizzy tablet. The salt lava lamp doesn’t look quite a good, and isn’t as reusable but is still a nice science activity for learning about density.

You’ll need

A glass jar or glass

Vegetable oil – or other cheap cooking oil

Water

Food colouring -optional

Salt

Instructions

Fill the glass or jar about three quarters full.

Top up with vegetable oil to almost the top.

Sprinkle salt slowly for about 10 seconds over the top of the oil.

Sit back and watch!

Keep adding more salt to keep it going.

Why does a salt lava lamp work?

Oil floats on water because it is less dense than water. Anything less dense than than water will float. We’ve demonstrated this before with a basic density jar.

Oil and water are immiscible liquids,