These yellow and red plastic counters are excellent for counting tasks and introducing probability.
Two-coloured counters feature one yellow side and one red side on the reverse. Use them for addition, subtraction and many more activities.
It measuring 25mm in diameter. Some activity ideas for bi-coloured counters:
Use the two colours of the counters to practise with positive and negative numbers. For instance: positive is yellow and negative is red. -2 + 3 would mean that you have 2 yellow and 3 red counters. A single positive and a single negative counter represents a sum of 0, and can therefore be ‘cancelled out'. What is left is one red counter, students can now visualize that the answer to the equation is +1.
In addition use the counters to practice with fractions: place 12 counters in 3 groups of 4, all with the yellow side up. What is the fractional portion of each of the groups of counters?
Flip one counter in one group (you will now have 11 yellow as well as 1 red counter). What is the fractional portion of the red counter within its group? And within the complete group of counters? Keep flipping counters to change the fractional portion.
Flip a counter 50 times and tally how many times it lands on red and how many times it lands on yellow. You should find it almost even between yellow and red. Now flip 2 counters and count how many times you have 2 yellow, 2 red or one yellow and one red counter. Do you see a pattern? Repeat with more counters, and predict the answer before you start.
Randomly place the counters on a table while letting students guess if there are more yellow or more red counters visible. Sort the counters by colour and count the counters to check the answer.