Rainbow in a glass

Type of resource: Website

Web address https://www.businessinsider.com/8-awesomely-simple-science-experiments-you-can-do-at-home-2016-7

Language: English

Description

Experiment – investigating the liquid density and the behaviour of liquids of different density when they come in contact

Scientific concept introduced

Density, dissolving, floating, sinking, liquid, collaborative learning, water, sugar, food coloring (food pigments), solutions.

Creative and critical thinking

Critical thinking- analyzing, comparing

Mathematical reasoning

measuring the amount of water and sugar, using the measuring cup, estimating, counting

Scientific thinking

Observing, predicting, concluding, formulating hypotheses

Learning how to learn

curiosity, motivation and engagement, reflecting on one’s own learning and knowledge.

Additional

A/ Oral language development – scietific vocabulary development;

B/ Teamwork – sharing ideas, accepting a leader and management, following the rules of safety and discipline

Rainbow in a glass

Overall aims

Enabling children to investigate the density of different liquids;
Creating opportunities to observe the behavior of liquids of different densities.
Developing the ability to listen and follow instruction.
Developing organizational skills and teamwork abilities.
Developing math skills – estimating measurements.
Delivering aesthetic opportunities to create “something beautiful” visually in an experiment: observing the rainbow.
Developing the ability to document one’s own work.
Stimulating group cohesion and building positive relationships between children.

Vocabulary – keywords should be understood

Density, dissolving, floating, sinking, liquid, collaborative learning, water, sugar, food coloring (food pigments), solutions.

Expected learning outcomes (operational aims)

The child will be able to:
– Conduct an experiment
– Examine the density of different liquids
– Describe the experiment, draw conclusions and document its course
– Listen and follow instructions
– Work in a small team
– Conduct a scientific observation
– Create “something beautiful”

STEM skills – to which the learning unit is related to

CORE STEM SKILLS

Critical thinking– analyzing, comparing

Mathematical reasoning: measuring the amount of water and sugar, using the measuring cup, estimating, counting

Scientific thinking Observing, predicting, concluding, formulating hypotheses

Learning how to learn: curiosity, motivation and engagement, reflecting on one’s own learning and knowledge.

ADDITIONAL SKILLS

– enriching scientific vocabulary
– teamwork,
– fine motor skills, and hand-eye coordination
– following the rules of safety
– documenting the experiment with drawing

Teaching methodologies/activity outline

Introduction:
Present the materials that will be used to carry out the experiment to children. Ask the question: “What do we usually do with this material?”
Explain that we will do an experiment called „Rainbow in a glass”.
The experiment will be used to investigate the density of liquids. (Everything will be given to the children)

Activity:
Explain what the experiment is about – show an instruction sheet, which should be discussed as useful material for the experiment. Then ask the children to work in teams. Each team will use its own material.

Material:
Transparent glasses (at least 1 per group)
Water
Sugar
Teaspoons
Plastic cups (4 per group)
Food colors (red, blue, green, yellow)
Needle-free syringes for dispensing water (at least 1 per group)
Experiment instruction sheets (1 per group)
Student’s notebook, scientific diary
Optional: camera and billboard to document the experiment.

Instruction:
1. Fill 4 measuring cups with the same amount of water and place them in a row. Question: How to pour exactly the same amount of water into each glass? Tip for the teacher: if you use cups without measures, you can mark the water level with a rubber or a marker pen.

2. Add 1 teaspoon of sugar into the second glass, 2 teaspoons into the third, and 4 teaspoons into the fourth.

3. Mix all the water and sugar solutions well. Question: Why mix the solutions well? Tip for the teacher: to dissolve all the sugar

4. Add food pigment of different colors to each glass, paying attention to the colors of the rainbow (red in the first glass, yellow in the second glass, green in the third glass, blue in the fourth glass).

5. Mix all the water, sugar and dye solutions well

6. Using a syringe without a needle, gently pour into the main glass in which you want to make a rainbow, first the blue solution, then green, then yellow and finally red. Question: Why do we pour blue in the first place? Tip for the teacher: Because being the densest solution, it will stay at the bottom

7. If the experiment is successful, we will observe the formation of a rainbow in the glass. The colors don’t mix. A rainbow will be created by the floating of one solution on top of another

Question: Does a real rainbow form the same way?

Teacher’s tip: No, a real rainbow is created by refracting light on water droplets.

Conclusions:
At the end of the experiment, the teacher should invite each group to take pictures to document the activity and possibly prepare a poster. Moreover, after discussing the experiment with the teacher, each child in a group should document the experiment on his/ her own worksheet (or draw the end results on a piece of paper). The “Rainbow in a glass” activity can be a starting point to offer other activities / experiments about the real rainbow (which develops thanks to the refraction of light) or to propose interdisciplinary activities.

Assessment of learning

Child’s observation chart – a drawing documenting the effects of the experiment, a photo of the results
Observation of children’s work by the teacher.

Equipment and materials to be used in learning unit (tools, ingredients etc)

clear glasses (at least 1 per group), water, sugar, teaspoons, measuring cups or plastic cups (4 per group), food pigments (red, blue, green, yellow), needle-free syringes for dispensing water (at least 1 per group), experiment instruction sheets (1 per group), paper and crayons, personal stationery

Optional: camera and billboard to document the experiment.