Adding and subtracting mentally worksheet

In a series of engaging mental arithmetic activities, KS2 students are challenged to add and subtract large numbers without the use of calculators. Activity 1 requires the use of randomly generated 5-digit number cards and ones, tens, hundreds, or thousands digit cards. Students work to mentally calculate the sum or difference of these numbers and write their answers on whiteboards, with the option to use jottings for assistance. The class then discusses the methods used to arrive at the answers, promoting a deeper understanding of mental calculation strategies.

Further exercises, such as Activity 2, involve similar tasks where students add and subtract smaller units to or from a 5-digit number and reveal their answers simultaneously upon the teacher's command. This not only fosters a sense of competition but also allows for immediate feedback and strategy sharing. Activity 3 adds a twist, where students select a number within a given range and aim to reach a target number through a series of four calculated steps, using addition and subtraction. Activity 4 expands on this by having students perform multiple additions and subtractions with different units around a central 5-digit number. These activities are designed to enhance the students' ability to perform mental arithmetic with increasingly larger numbers, a key objective in their mathematical development.