Description of activity
Students determine a method for mixing paint to vary colour.
This activity will take approximately 1 hour.
Students will have been learning about fractions and are familiar with the fractions of a half, a quarter and an eighth. They observe a painting, eg La Seine à Rouen that shows a number of different tints and shades of the same colour. Students use their knowledge of fractions to mix a colour with white paint to make a number of different tints of that colour.
Knowledge and understanding
- An artwork/painting that shows a variety of tints and shades of a particular colour
- A variety of colours of acrylic paint with a greater quantity of white, plain wooden toothpicks or paddle-pop sticks for mixing paint (at least 4 per person), small containers or palette to mix paint
- Containers used for measuring, eg plastic teaspoons (at least 2 per person)
Work, health and safety
Check relevant Work, health and safety guidelines.
Evidence of work for assessment purposes
- At least four different tints of a particular colour painted on paper and/or on mixing sticks, labelled as a fraction of the colour
- A written record of the method used to mix paints to produce these different tints
- Student-made artwork based on use of tints and/or shades of a particular colour
STEM teaching and learning activities
- Students observe artworks which show a number of tints of the same colour.
- Discuss how the artist may have made so many tints of the same colour. Some students may suggest mixing paints of different colours or mixing them with water. Elicit as many different responses as students can suggest.
- Students plan how to make a colour of a lighter tint. Students record their plan.
- Students paint an area on their paper in the original colour and label it 'original'.
- Students choose a colour and get 1 measure (eg teaspoon) of that colour and follow their plan to get a lighter tint. Paint an equal area on their paper and label it 'first tint'.
- Students compare tints and the method they used to obtain the tint.
- Explain that a 'tint' is made by mixing a colour with white paint.
- Pose the problem – 'If an artist wanted to make lighter tints of a colour and be able to make that exact same colour again; how could they do this?'
- Students devise a method that would provide them with a colour half as strong as the original colour.
- Teacher guidance may be necessary to enable students to realise that mixing equal quantities of the colour and white would give the desired tint.
- Teacher leads a class discussion on the meaning of fractions, eg if the pure colour can be taken as a whole, then taking equal quantities of the colour and white, means that the colour now is one of two parts of the mixture. Thus it is half as strong as the original whole colour.
- Teacher models mixing other fractions, eg one part colour mixed with three parts white paint will produce quarter-strength colour. One part colour mixed with seven parts white will make one-eighth strength colour. These tints can be made in quantities that are needed for the class.
- Students add these extra tints, with labels, to their notes.
- Students make their own artwork using the tints.
Fraction – a part of a whole or any number of equal parts
Hue – a mixture of two primary colours
Mixture – something made by combining two or more ingredients
Primary colours – red, blue and yellow; cannot be created by mixing other colours
Secondary colours – purple, orange and green; mixtures of any two primary colours
Shade – a mixing result formed by adding black to an original colour
Tint – a mixing result formed by adding white to an original colour
Key inquiry questions
How will you make sure that your mixtures will be the same each time they are made?
This is where the student's knowledge of fractions plays a part. The original colour would be full strength. Taking one part, eg one teaspoon of the original and mixing it with one part (one teaspoon) white will make a lighter tint of the colour. The colour will be half-strength. Continuing this procedure is how pastel colours are made.
Writing a procedure or method
When writing a practical method, students use numbered steps rather than prose. Start each point with a verb rather than 'I did' or 'you should', eg 'Mix one teaspoon of' – use precise measurements where possible.
Students explore the idea that one-half is one part out of two parts; one-quarter is one part out of four parts and one-eighth is one part out of eight parts. Other fraction equivalences can be explored.
The following statements outline some common preconceived ideas that many students hold, which are scientifically inaccurate and may impede student understanding.
In everyday language we use the term 'shades' to refer to different intensities of colour. Using correct art terminology:
- shades of a colour are made by mixing that colour with black (as in shadow) making the colour darker
- tints of a colour are made by mixing a colour with white, making it lighter.
While it is not a misconception, many students have great difficulty with the terminology used to describe fractions, eg ¼ means one part in 4. Students also have difficulty with the equivalence of fractions, eg ¼ equals ½ of ½.
The terms 'numerator' and 'denominator' are introduced in Stage 2.
- Count Me In Too building fractions through equal sharing
- Alien Fractions short student video
- Wholes, Halves and Quarters short student video
Adjustments for the diversity of learners
Students complete the same exercise making 'shades' of the colour by mixing the colour with black paint.
Students use samples of their shades and/or tints to make a scale of colour.
Use different mixtures and proportions of primary colours. The primary colours are yellow, blue and red. By mixing different primary colours, eg yellow and red, students can form different secondary colours. By varying the proportions of those primary colours students make different 'hues' of colour from yellow through orange to red.
By completing this STEM activity, your students have been provided with the opportunity to develop an understanding of fractions. Students will learn to manipulate and equate fractions throughout their mathematical studies, culminating in Mathematics studies of trigonometry and algebra.
Your students have devised and described a method for producing different tints of a colour and related their mathematical knowledge to solve a problem relevant to many artists.