Here are some of the particularly successful activities that I prepared for my group, which has 4 to 8 year olds in it.
1) Play-dough Blood Model
This was a fun group activity. First, I explained about the different parts of blood using the Usborne First Encyclopedia of the Human Body. Then we spread out yellow paper as plasma, made red blood shells by rolling balls of red play-dough and making an impression in the balls, then made a few large white blood cells from white play-dough, and finally used blue play-dough to make platelets. As we we went along, I reminded the children of what each blood cell type was for.
2) Cake Model of the Heart and Lungs
I made cakes the right shape ready - 2 lungs and a heart, and had a rough sketch of what the final design of each piece should look like. I divided the group into 3, so I had a small group working on each cake. Each group was given fondant to in the right colour to roll out (or beat flat in the case of one enthusiastic group of 8 year old boys!) and cover their cake with, sticking it on with jam. They then used tubes of icing and strawberry laces to draw on the blood vessels (following the design I gave them). It worked even better than I hoped!
3) Red Cabbage Indicator
This was surprisingly simple to do, and very effective. I got the children to make their own indicator, as this seemed like more fun. The children tore up red cabbage leaves into a large plastic cup, then I added hot water for them. We left it a minute or two before sieving the liquid into a fresh cup to remove the leaves, then used a pipette to transfer small amounts of the liquid into small plastic cups so that different substances could be tested (I bought disposable shot glasses). The children then tested vinegar, cream of tartar, lemon juice, water, bicarbonate of soda, soap, and cif cleaner.
4) Light-Up Battery Bugs
The idea is that you tape a light bulb to the top of a battery, then tape wires to make antennae so that they complete the circuit if they are connected by a conductor. I took the idea from a (generally excellent) Usborne book, 100 Science Experiments:
It turned out much more fiddly to get working than I expected, which involved quite a lot of work the night before getting the bugs half made so that they would work most of the time. Nonetheless, they were very popular, and did help the children learn more about electricity.
5) Models of Plant and Animal Cells
The children made 3D animal cell models out of jelly and sweets (after learning about what the different parts do).
They also made models of plant cells out of paper plates.
When we did this at the group, I gave them the paper plate activity first; if we began with sweets and jelly, it's unlikely that the next activity would be sufficiently enthralling!
6) Is it Magnetic?
This was a simple activity to prepare and to execute, but which went down well with the children - which was good as this was for our last session of term when I was feeling pretty tired!
First, I scattered a selection of household objects round the room, each with written label beside it to help the children match the objects to their list.
I gave the children a chart to fill in with a list of the objects, and two separate columns to fill in. First, I asked them to predict whether an object was magnetic or not. Once they had completed that column, I gave each child a magnet to use for testing.
Although this was simple, it was still fun and hands-on, so it went down well.