We’ve noticed a lot of great books that have been released recently aimed at primary age children (under about 11). We thought it might be useful, for those who know children of those ages, to put together a list of these titles, and some classics, in case you might be looking for some gift ideas around now.

## You're reading: Posts Tagged: numbers

### Mathematical Objects: Number block cubes

A conversation about mathematics inspired by number block cubes/snap cubes. Presented by Katie Steckles and Peter Rowlett.

Peter’s blog post: Mathematical play with young children.

Mike Lawler’s three-tweet thread of more advanced ideas starts here:

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### HLF Blogs – The numbers behind the young researchers

*This week, Katie and Paul are blogging from the Heidelberg Laureate Forum – a week-long maths conference where current young researchers in maths and computer science can meet and hear talks by top-level prize-winning researchers. For more information about the HLF, visit the Heidelberg Laureate Forum website.*

Having extensively covered the talks and press conferences of the Laureates so far, we thought it was time to talk to some of the Young Researchers at this year’s HLF about the work they’re doing.

### Mobile Numbers: Multiples of nine

*In this series of posts, Katie investigates simple mathematical concepts using the Google Sheets spreadsheet app on her phone. If you have a simple maths trick, pattern or concept you’d like to see illustrated in this series, please get in touch.*

We’re all (hopefully) aware that a pleasing property of numbers that are divisible by nine is that the sum of their digits is also divisible by nine.

It’s actually more well known that this works with multiples of three, and an even more pleasing fact is that the reason three and nine work is because nine is one less than the number base (10), and anything that’s a factor of this will also work – so, in base 13, this should work for multiples of 12, 6, 4, 3 and 2. Proving this is a bit of fun.

Once when I was thinking about this fact, an interesting secondary question occurred.

### Follow Friday, 21/03/14

It’s been a while since we’ve done one of these, but here’s a selection of Twitter accounts you may wish to follow. This week, the theme is numbers!

36871

— Prime Numbers (@_primes_) March 14, 2014

While I usually try to pull out an interesting tweet to showcase the brilliance of the accounts I recommend, in this case the account is tweeting every prime number. It’s run by an automated script, which you can see the code for, and according to its bio, aims to tweet “Every prime number, eventually”. Ambitious.