Algebra...substitution

We have been working on algebra in our maths lessons this week. This has included forming algebraic expressions, solving and creating formulas, and understanding and using substitution. Substitution is where the children are provided with an expression such as a + b, but this has no answer. They are then told the values of a and b. They must then substitute in these values to work out the answer. The children then looked at how the result of an expression can change depending on the value.

e.g. 3a + 5...If a = 5, then the answer is 20. If a = 7, then the answer would be 26. 

Once they had completed the Main Task, the children worked in pairs to create their own algebraic expressions with symbols and letters to represent the numbers. They had to think carefully about whether our equations would work before giving them to their partner.