I want to bring this blog to note because I think it would be far more cost effective when we usually demonstrate how plants absorb water. Normally, we buy a bunch of flowers and either put them all in one vase of artificially coloured water, or separate them between two colours. Normally only blue and red. We might also do the same with a packet of celery. Celery is good because you can cut the stem and see the colour going all the way through.
However, I was drawn to this particular blog and the idea from a photo of cabbage leaves in different coloured water. With celery, only blue and red ever tend to really work, visibly. Well, Paging Fun Mums has clearly got red, blue, green and yellow to work amazingly well with cabbage leaves. I also think that it would be far easier to ensure a whole class could set up their own set as a cabbage would go further than a bunch of flowers. They were apparently only left overnight, which is probably what we would do.
I just really want to try the cabbage!