Elements, molecules and compounds
lots of balls.... the ones for babies ball pools. They sell them in toy aisles of supermarkets and are fun for lots of things. Use a glue gun to join them together as examples of different molecules. They can also be alpha particles, and little polystyrene ones beta particles.
Elements bingo - cards printed with symbols, pupils have a periodic table, but it is played at a fast pace so they have to be quick.
When I did atomic structure I used a version of the Adams family song, aptly called the Atoms family, along with a story. The song sheets are stuck on my wall and every class I have beg me to allow them to sing it.
The Atoms family
They’re tiny and they’re teeny,
Much smaller than a beany,
They never can be seeny,
The atoms family.
Chorus
They are so small (clap clap)
They’re round like a ball (clap clap)
They make up the air,
They’re everywhere
Can’t see them at all.
Together they make gases
And liquids like molasses,
And all the soild masses
The Atoms family.
Chorus
Neutrons can be found
Where protons hang around
Electrons they surround
The atoms family
Chorus
http://sciencespot.net/Pages/classchem.html#Anchormixtures
For diffusion my bottom set year 8 will remeber it for ever....i got a really nasty can of body spray and aftershave for xmas...I spray loads of it in the corner of the room and get them to put their hands up when they can smell it...it really is nasty stuff the kids moan but they remeber what it is....and if they moan to much i threaten to spray them with it...
A rainmaker from Argos is also fun for demos...it can be used for diffusion and osmosis if you turn it on its side and rotate it. The little ball bearings which you say represent the molecules move from high conc to a low conc...also makes a pretty noise and can also be used as a timer....
I have just bought a 'beanie baby' a rainbow coloured Ram. yes I have been teaching relative atomic mass and I got the kids to draw a tiny ram and label it H, one twelve times bigger and label it C and one sixteen times bigger and label it O. After marking the books I felt they might need to know what a Ram is as I had all sorts, Rhinos, stick animals and my favourite three clouds. Ok yes I did say draw a cloud and add legs and a head the crucial part being ADD legs and head.