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Forthcoming Workshops
Mathematics HL
IBDP Category 2
Barcelona, Spain
6 to 8 October 2017
more info
Mathematical studies SL
IBDP Category 1
Barcelona, Spain
6 to 8 October 2017
more info
Mathematics SL
IBDP Category 1
Barcelona, Spain
6 to 8 October 2017
more info
Find all InThinking Workshops at www.inthinking.net
Site Author
Tim Garry is the site author and has taught mathematics from middle school to university since 1984 and been Head of Maths at three international schools. He's also been an IB examiner for external & internal assessment, contributor to IB curriculum reviews & Maths HL exam writing teams, delivered numerous workshops & coauthored IB maths textbooks (see below).
moreQuote of the day
Many who have had an opportunity of knowing any more about mathematics confuse it with arithmetic, and consider it an arid science. In reality, however, it is a science which requires a great amount of imagination.
(Sofia Kovalevskaya, 18501891)
Resources
Standard Level Mathematics
Textbooks for Math HL and Math SL. Two textbooks written by Tim Garry and Ibrahim Wazir that are fully revised 2nd editions providing comprehensive coverage for the new 2014 syllabuses. Each textbook comes with an ebook (accessed through a website) containing a complete digital copy of the text along with numerous additional material.
School visits
If you are interested in Tim Garry visiting your school to work with teachers and/or students, please contact us.
Home2Home
The vacation home exchange service for the IB community.
Feel at home when you travel the world.
www.home2homeinthinking.co.uk
Problem of the Day
There are now 100 problems (50 SL + 50 HL) on this page  and more to follow. Starting May 1st, the Problem of the Day lists will not be on this page, but on subpages. A subscription to this site will be needed to access these pages. Below you will find two growing sets of 'problems' (one for SL and another for HL) with one new 'problem' added nearly every day to each set....
Recommendationsmore
I highly recommend any IB Mathematics teacher who is seeking expert guidance on how best to teach either Standard Level or Higher Level Mathematics in today's classroom to subscribe to the InThinking website. It is an invaluable resource for both...
Tim's InThinking site has been invaluable to me as a new IB teacher. Before starting any new syllabus item, I use the site to gain a better understanding of the types of problems that my students need to be able to solve. It has helped me to format...
I love the "accessible" to "discriminating" levelled questions. They are great for differentiation in the classroom  especially as time in the IB classroom is so precious. Students start work at their own comfort level, discuss in...
Blogmore
Challenge Problems (#10)
Sunday 10 April 2016
To me  and to most people who enjoy mathematics  solving a problem that requires insight, perseverance and creative use of mathematical knowledge... more
Measuring the earth's radius 1000 years ago
Tuesday 10 November 2015
This past weekend I was reading a review of a new history book, The Silk Roads by Oxford historian Peter Frankopan, in which the reviewer states... more
Perplexing Pentagons (Exploration Idea #499)
Sunday 13 September 2015
Recently, a Maths SL student asked for my thoughts about her writing an Exploration (IA) on tilings of the plane (Euclidean tessellations).... more
Subscriber comments

I've managed to fix all the math expressions/equations on this page. It's quite a long page, so I'm thinking of splitting it into three different pages.

I endorse K.Young´s comments...

In problem #3 of the practice set 51, the calculation of median should be (2+3)/2.

Hi Tim Thanks for putting some extra time in my life! It was so helpful to have two good mock exams for HL that the students did not have access too. We have enjoyed all of your work and my HL classes have benefitted from your efforts. Thanks...

Hi Tim! Also think there might be a small mistake in the number of marks on the mark scheme for SL Paper 1, 2017, Question 6: it should be worth 6 marks but there are only 5 marks on the mark scheme. Thanks so much for these! I am marking...

Do you have a worked solution for the Airship problem (#6 on EXS_4140v1_SLHL_vectors_review)?

Expectation Wkst Error? .... Var(J) = 2, Var(K) = 1 ... solution 9x2 +16x1 = 34

Sorry  hit "submit" before it was finished. This affects the probability that X is between 160 and 180  that should be 0.80. But then how can Prob (160 X 185) be 0.75?

Hi Tim  I think there might be an error in question 9, 2017, SL paper 2. If P(X

Cara, Oops  sorry about that. I've now uploade a new 'version 3' of the Solution Key for the P3 mock exam with answer (not really a worked solution) for Q.2(b).

Thank you for the Mock Exam, I see the solution to 2b is missing.

My grade 11 students also have "enjoyed" them  I choose the questions that address topics we've already covered  never too early to revise! Thanks, Tim!