Modelling Genetic Drift with M&Ms


Genetic drift is defined as random changes in allele frequencies in a population. It occurs in all populations that are not infinitely large and has a particularly strong effect on small populations over several generations. Because genetic drift is a random rather than deterministic process like natural selection, students often have a difficult time understanding and appreciating its role in evolution.

This simple exercise offers an active learning approach by simulating the founder effect and bottleneck effect (two examples of genetic drift) using M&Ms. A worksheet with full instructions, examples of discussion questions and data sheets is available to download in full from here.


Desert Island Apps for Teachers


There are thousands of websites and apps aimed at teachers but if you had to pick just 10 that you couldn’t live without – the digital bare essentials of a 21st Century classroom, your desert island apps – what would they be?

Here, in no particular order, are mine.

1. Google Drive and Google Classroom

Google Drive includes Google Docs, Sheets, Slides and Forms as well as many other GAFE (Google Apps for Education). Google Classroom is a learning platform for schools which brings it all together in a secure online environment. Drive and Classroom allow students to collaborate and share files quickly and teachers to create and distribute assignments, flip learning, grade work, and post notices. Indispensable.

2. Kahoot!

Without doubt this would be the students’ choice. Kahoot! is an enjoyable, game-based learning platform with many similarities to (the also excellent but less jovial) Socrative. Use it to build fast paced multiple-choice quizzes and class surveys or pose questions at hingepoints during a lesson to receive instant feedback from all. Formative assessment at its most fun.

3. TES Teaching Resources

If you didn’t already know, TES Teaching Resources is a vast online library of mostly free lesson plans and classroom resources uploaded by teachers from around the world. To be honest, it’s not all great but there are some real gems in there which are more than worth the rummage. The site is also home to Teachers’ TV; a source of high quality videos on teaching and learning in Early Years, Primary, Secondary and FE, as well as films to help with continued professional development.

4. Adobe Voice

This one is relatively new on the scene but I love the simplicity of this application for making short, highly-professional-looking animated videos. I have written about it many times in this blog and confess to being a huge fan.


This site provides a variety of different stopwatches and clocks which can be used to add a sense of urgency to any starter activity or plenary, help keep younger students on task, or be clearly displayed during classroom-based tests.

6. Educreations

There are now a huge number of apps for creating video tutorials on the iPad but I have mostly remained faithful to Educreations as it works seamlessly with Google Drive and is so simple and intuitive to use. As well as making tutorials, I find it useful for providing feedback on larger pieces of student work (e.g. posters or models). I simply take a photograph, import it into Educreations, and then comment and annotate over it before sharing with the student via Classroom.

7. Twitter

We all know that Twitter is essentially a virtual staffroom for sharing resources, airing opinions and generating discussion but it can also be used to support learning in the classroom. For example, I have used it to provide a running news feed, tracked hash tags, connected with other classrooms and industry professionals, and encouraged students to send live Tweets during field trips. There are lots of possibilities. Not convinced? Here is a useful post by the brilliant @ICTEvangelist on the dos and don’ts of getting started in the pedagogical Twittersphere.

8. Armoured Penguin

The best site I have found for making crosswords and other simple word games. All free and easily converted into PDF.

9. YouTube

Create playlists of videos on particular topics, import videos into Google Forms as a flipped learning activity, post video tutorials, find sound effects to really bring your lessons to life, or simply mine this vast resource for educational audio visuals. TeacherTube, TedEd, How Stuff Works, BBC and Sick Science are just some of my favourite channels.

10. Visible Body 3D Human Anatomy Atlas

This is the only subject-specific entry on my list and a costly one (at the time of writing £18.99 from App Store) but it is a simply stunning piece of kit with an impeccable 3D interface offering students a far greater appreciation of anatomical structures than the flat drawings of a textbook ever could. The high-resolution graphics offer smooth zooming, panning and rotating capabilities and the concise labelling (showing the name of each structure and the system hierarchy to which it belongs) make it particularly useful for older students during organ dissections and demonstrations. Brilliant.

So there you have it, my top 10 teaching websites and apps. I would love to hear about your own desert island choices!


CIE Mark Scheme Abbreviations


Some students (and teachers) remain confused by the abbreviations used in mark schemes. Since completing and then marking past papers is a key element in effective revision for the upcoming examinations, I thought it timely to highlight the following conventions used by Cambridge International Examinations (CIE) at both IGCSE and A Level.

+ ,  

All parts of the answer separated by a plus sign or comma are required to achieve the mark. In the example below, the candidate must refer to assimilates or sucrose and to the fact that they lower the water potential (inside the sieve tube element) in order to gain one mark.


( )

Information in parentheses does not need to be made explicit in the answer in order for the candidate to achieve the mark/s. See example below.


Alternative answers for the same point. In the example below, the candidate can make reference to either folding or coiling and does not need to mention the tertiary structure (in parentheses) in order to be awarded the mark.


Separates marking points. In other words, semi-colons represent the number of marks available for each answer. Note, that for the example below, full marks are available just for giving the answer (300) whether or not the candidate has also shown their workings out.



Accept. The answer is not the answer the examiner is looking for but has been correctly cued by an equation or extra guidance and therefore acceptable to achieve the mark.


Any Valid Point. One point (note the one semi-colon) can be awarded at the examiner’s discretion if any other valid point has been made by the candidate.


AVP ;;

Any Valid Point. The examiner can award up to two marks (note the two semi-colons) for two valid points made by the candidate.


Reject. This is different to ‘Ignore’ (I) and is a negative marking system. In other words, a mark must be deducted from the total if a ‘Reject’ answer is given. In the example below, if a candidate wrote ‘antibodies produced by T-cells‘ they would not receive a mark (i.e. the point awarded for correctly answering that antibodies are produced is deducted for incorrectly stating that they are produced by T-cells).


Alternative wording. This is used when the responses are likely to vary more than usual. For example, instead of saying ‘less oxygen enters the blood‘ it would be acceptable to answer ‘less oxygen passes into the blood‘ or ‘less oxygen diffuses into the blood‘ etc.


Answer underlined

These are key words which must be used by the candidate in order to achieve the mark. Note that grammatical variants and spelling errors (so long as the word can be read phonetically) are accepted.


Or reverse argument. The reverse argument is equally valid.

I hope this clears up any confusion but if you have any questions about mark schemes and script abbreviations or conventions, please do get in touch.




Awesome Lesson Starters

Start the lesson with a bang!

What students experience in the first couple of minutes of a lesson makes a crucial difference in how well they engage with the learning intentions and as such, starter activites should be exciting, enthusing and unpredictable.

Here are some ideas for creating that ‘hook’ and maintaining the curiosity of students from the get-go.

  • Start the lesson with a fun or even explosive demonstration which ties in to the main body of the lesson. Sick Science has lots of great ideas.
  • Pass around mystery objects inside sealed bags. Ask the students to guess what they are and what they do.
  • Display apparatus, interesting objects and photographs around the room.
  • Play a short video on a loop and hand out questions about its content. This is even better if it is a video that you or the students have made. For example, a time-lapse video to recap the previous lesson or the steps of a practical investigation presented in Adobe Voice.
  • Write a true / false question or a statement on the board. As pupils arrive ask them to choose whether they think it is ‘true’ or ‘false’ or whether they ‘agree’ or ‘disagree’ and to stand to one side or another of an imaginary line down the middle of the room.
  • Display a picture and a question. Alternatively, you can display a number of different pictures related to a theme and simply ask ‘What have I Googled?’
  • Play ‘Backs to the Board.’ Divide your students into two or three teams. One volunteer from each team sits in a chair with their backs to the board, facing their friends. Write a key word on the board, making sure that the players in the ‘hot seats’ can not see it. After you say ‘Go!’, the members of each team must try to elicit the word from the volunteer without saying the word or giving any clues as to its spelling. The players in the ‘hot seats’ then swap with another member of their respective teams.
  • Arrange for a guest speaker to be standing in the room as the students arrive.
  • Recap the last lesson by displaying true / false statements or multiple choice questions and asking students to answer on mini whiteboards.
  • Use Socrative or Kahoot to prepare a fun quiz or questionnaire.
  • Play a song relating to the lesson as the students arrive.
  • Display multiple choice questions around the room. Give the students a time limit (these classroom timers are fun) and get them to move around the room looking for and answering the questions.
  • Set up apparatus for the lesson and display one or more questions about what it might be for and how it works. Alternatively, hide the appartus under a cloth and, before revealing it, ask questions about what it might be.
  • When they arrive, hand each student or pair of students a mystery object and ask them to come up with ideas about what it might be used for.
  • Greet the students at the classroom door wearing full protective equipment including visor or goggles.
  • Hand each student a question or an answer to a question and ask them to find their pair.
  • Play the ‘Who Am I?’ game but instead of a famous person designate each student a key word relating to the current topic. Remember, participants can only use ‘Yes’ and ‘No’ questions to work out who or what they are.

No matter how you start the lesson try to involve the students whenever you can and make sure it does not go on for too long. Link the activity to the main body of the lesson and allow time for questions and answers. Have fun!


This fun game-based learning platform is simply the most popular app I have ever used in the classroom.

Kahoot! is actually very similar to another of my favourites, Socrative. The teacher (or students) creates a multiple-choice quiz using the web interface which students then access using their tablet, laptop or smartphone. There are also thousands of ready-made public Kahoots that you can use.

However, unlike Socrative, the questions are only displayed via the teacher’s device and the students answer by selecting one or more of four coloured buttons that appear on their own screens (see below). A time limit, a leadership board and the fact that students can get more points by answering quickly adds a competitive element which the students adore.


Kahoot! can also be used as an interface for class surveys and I have recently started using it to display hingepoint questions during lessons as a means of formative assessment. It is completely free and although registration is required to create quizzes, students are not expected to login to play (they simply tap in a pin number displayed by the teacher). I highly recommend it.


Lemonade Bottle Ecosystem

This is a wonderful activity in which students build a self-sustaining ecosystem containing primary producers (microscopic algae), primary consumers (brine shrimps) and decomposers (micro-organisms) inside a lemonade or coke bottle.

So long as you leave the bottle ecosystem on a sunny windowsill, the brine shrimps never require feeding and never run out of oxygen because the photosynthesising algae on which they feed, multiply by asexual reproduction. In turn, the algae never runs out of carbon dioxide, water or mineral salts because they are all recycled.

A book produced by Stephen Tomkins and Michael Dockery entitled ‘Brine Shrimp Ecology – a classroom-based introduction to ecology‘ is available to download copyright free from the British Ecological Society and contains a plurality of resources for ecological investigations including teaching notes, technicians’ guides and background information. The activities are primarily aimed at key stage 3 and key stage 4 students but could also provide the starting point for post 16 biology projects.

Blades Biological (based in the UK but accepting international orders) can supply brine shrimp eggs and algal cultures to get you started.


Interactive Models of the Human Eye

There are some excellent interactive guides to the human eye available online. I have used them in class but also as the basis of a flipped learning activity which I then followed up with an eyeball dissection and this highly effective model eye demonstration.

This resource from Lenstore takes you on a journey right through the centre of the eye from the cornea to the optic nerve. Pop-up labels provide a brief outline of each part of the eye but these can be expanded to find out more.


Contact lens manufacturers Acuvue provide another interactive model as well as video tutorials and diagrams explaining the causes of nearsightedness and farsightedness and the ways in which they can be corrected.


VisionDirect also offer an interactive model with more simple explanations, more suited for Key Stage 3 learners. There is also a worksheet to accompany it.

eye 2


Science and Plants for Schools (SAPS)

I highly recommend the Science and Plants for Schools (SAPS) website. It is packed full of very high quality teaching and learning resources including set practicals, videos (like the one above), journal articles, science club ideas and presentations. It also hosts an extensive image library. Sign up for their free newsletter to be the very first to hear about exclusive opportunities and grants, a round-up of the latest research and even more inspiration for your teaching.