Have you heard of the Cambridge Chemistry Challenge? If not, it is definitely worth a look (http://c3l6.com).
The website is primarily aimed at UK students in the ‘lower 6th’ – this is equivalent of IB1 but the chemistry itself is very worthy of all IB students and is open to students in the UK and from around the world.
In order to fully access the website you will need to register (for free) – if you don’t want to do this though, there are still many good resources that are free to download (and challenging!)
There are a few layers to the website.
Every month a Chemistry challenge is released. The challenge works by releasing a picture / cryptic clue to an element or molecule each month. Students are able to study the clue and then submit an answer. There is also few resources periodically released (eg, understanding skeletal formula).
However, in my opinion, the best resources are the exam papers (and mark schemes, phew!)
Every June a paper is released. Students are free to sit the paper. You, the teacher then (if you wish) can mark the paper (this is usually very quick) and send off the papers and marks to the Royal Society of Chemistry who are responsible for writing the papers.
Any students reaching a predetermined mark (not released) are eligible for a reward and certificate – there are various levels to be reached according to the students final mark ranging from copper, silver, gold and if you are top dog roentgenium.
It is no mean feat to achieve any of these awards, last year over 40% of entries were not of a high enough level to get the copper award, with less than 1% of entries receiving the prestigious roentgenium award. Successful students are sent a certificate and if a student is considering a degree in chemistry, it is something they can add to their university application.
The questions are often long and wordy (a bit like paper 3) but the students are tested on good chemistry – and good chemistry is always supported in their answers. They are topical and based on current new items (eg, a question from June 2014 talked about the use of beryllium in the James Webb Space Telescope). The questions are cover many different topics, for example moles, bonding, organic, thermodynamic, all in one question. If a student can’t complete one section of a question, they are possibly able to complete another.