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Rounding and Estimation with MAB

MAB blocks can be used in so many places in the maths classroom! Who would have thought they could be used for rounding and estimation?

Thank you for MathsPathway for this little beauty of a lesson using MAB blocks and playing cards or dice. The first step is to turn over two sets of two playing cards (or roll two ten-sided dice) to create a couple of 2 digit numbers to multiply together. In the first column of the downloadable template sheet students write the muliplication :


The next step is to round the numbers to the nearest ten and write the rounded multiplication in the middle column. Students can use the downloadable rounding grid to help with this if needed:


Finally, students complete the rounded multiplication The MAB blocks really help students to visualise the muliplication and find the answer, or at least check their answer:

Here's another one with even larger numbers:



Please comment below with where you think I could go from here in my next lesson!

Comments

  1. Math Facts Game teamOctober 13, 2026 at 4:58 AM

    I’m affiliated with Math Facts Game. For a next lesson, you could keep the rounded estimate fixed and change the original factors: 21 × 31 and 24 × 34 both round to 20 × 30, yet their exact products are 651 and 816. Before calculating, learners could decide which rectangle needs the larger extra strips around a 20-by-30 block model. That connects the estimate to the exact product and gives a reason to discuss why two answers can share the same estimate. This is a suggested activity, not a report of classroom use.

    ReplyDelete
  2. Mathematically SpeakingOctober 13, 2026 at 8:39 AM

    Hi Maths Facts Game Team! Thank you so much for your reply, what a fantastic idea for a class activity. If any readers would like to try this activity please reply with how you went!

    ReplyDelete

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