Free Week 9 GCSE/iGCSE Biology lesson: photosynthesis, limiting factors, a pondweed practical, and the 17th-century willow tree experiment that got it half right.
Unit 3 begins: Ratio & Proportion. This week covers what ratio actually means, how to simplify it, share an amount using one, and solve problems when you're only given part of the picture — genuinely practical maths that shows up everywhere from recipes to exchange rates.
