Adding Multiples of 10

We spent the previous week or so recapping and strengthening their addition/subtraction skills by way of worksheets, number lines and mental maths - but always questions with 1-digit numbers (either +/- 1-digit, or +/- 2-digits).

This week, I want to focus on questions involving 2-digit numbers.

We began by getting the multilink cubes out and sorting them by colour into lines of 10. We did some simple addition sums using each stick to represent 1, e.g. 2 + 4 = 6. Then I asked them how many cubes were in each stick? 10. So what we actually did was 20 + 40 = 60. (The girls are already confident counting in 10s, which I think is a prerequisite for this activity). As we did each example in multiples of 10, I wrote the sum on the whiteboard using different colours to highlight the 0 as a placeholder.

Once they seemed like they had the hang of it, I wrote a question on the board without the colour coding and asked them to use the Multilink sticks to help them calculate the answer. MashaAllah, this whole bit of teaching took them less than 10 minutes to grasp.

Finally, I gave them the above two pages to complete. I sat with them as they did the first sheet (CGP Key Stage One Maths - The Question Book) then left them to do the top half of the second sheet (Letts Make It Easy... Maths & English (Age 5-6)) individually. For the second half of the sheet, I guided them in how to answer the first question, showing their working out, then let them answer the rest themselves.