Wednesday, 10 October 2012

Jelly on a plate

Long time readers may remember that I used to perform many and various experiments with my children. That's working with them to investigate scientific questions. Not using them in experiments. That would be wrong.

Time passed and I started to volunteer as a classroom helper for all the science classes at school, and for a while jointly ran an after school science club where the children could explore the fun parts of science that were outside the national curriculum. We set fire to things. We built rockets. We looked at the planets. We made a lot of edible experiments. And I stopped blogging about child friendly science, because there are (quite rightly) rules about writing about other people's children.

Anyway, I have missed it, and as they've got older my girls are starting to want to explore vile and strange experiments again at home, so here we have, just in time for Halloween ... exploding gummy bears!

This one couldn't be easier. Get yourself some Haribos (other scary jelly sweets are available), pop them in water, and wait for 24 hours. Make sure you keep some unsoaked ones for comparison - in many ways introducing the idea of a controlled experiment is for me the most important scientific concept my children gained from this one.


The reason they do this is down to the weird properties of gels - they behave like solids but are actually cross linked polymers (long molecules) that can hold large amounts of liquid; in practice the jelly sucks up water like a sponge. Those water releasing crystals you get for pot plants do the same thing, and anyone who has been amazed by just how full a disposable nappy can get has witnessed gel chemistry in action.

The texture of these is utterly bizarre. The children tell me they taste revolting (I think they start off revolting but that's just me) and some of the lads at school have found that if you leave them longer they begin to disintegrate. This has led them to think of more ideas for experiments - what happens if we let them dry out? Can we filter them? Would they swell faster in warmer water? How about in the fridge? What if we put them in a different liquid? Would jelly beans do the same thing?

I have other ideas up my sleeve in time for Halloween. If I can convince them to join in, I'll let you know.

23 comments:

  1. I am putting Haribos on the shopping list to try this!Scienec is my daughter's favourite subject thanks to her inspiring teacher last year, so she'll love this.
    Yes please to more science geekerey! xx

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  2. Fabulous! Yet another thing on my list of things to do with J. Do please keep sharing your science experiments - it's J's favourite subject. R xxx

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  3. See, now this explains why the gummy fish swimming in blue jelly party jellies I made were so blooming nasty! The amount of food colouring I used also made the kids poo a ludicrous colour, but that is, perhaps, too much information!

    I was so happy to see your post pop up!

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  4. Somehow, this little experiment has made gummies even more un-appetizing than they are to start with LOL! (Keep up the fun though!)

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  5. Yay, I do love your experiment posts Val and I did have a giggle at your opening paragraph, good thing you clarified that! Toby is very partial to haribos and given the chance will consume a large quantity in one sitting but I will be regulating his consumption more strictly in future having seen how much they grow! Good luck with your halloween experiment planning - I'd love to see what you are thinking up.

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  6. ooh you can't beat a bit of science fun to get kids excited :-) Will have to try that one. How about playing with corn flour - that stuff is amazing :-)

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  7. Yippee. I can't wait to get going on this.
    Hope all happydappy over with you, Ax

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  8. I will have to tell my youngest (who is 23) this is right up his street and knowing him he'l eat the sweets when he's finished blowing them up.

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    1. It also works with vodka... which may be even more up his street?

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  9. My daughter was playing with haribos (any excuse) the other day. One of the hearts was soaked overnight in water .. looked seriously repulsive 24 hours later and then it got put into the freezer for yet more torture. Personally, I would have just eaten it .. hearts are my favourites. After the fried eggs of course !

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  10. I have accidentally experimented on a disposable nappy by gathering one up and putting it through the washing machine on a cottons cycle. That gel really does expand, and boy does it get everywhere!

    We are definitely trying the haribos thing, what fun! I think you should start an online children's science club. My children would definitely sign up!

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  11. Excellent. Just need DDs to come home now so that we can start to play. Thanks for sharing!

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  12. The best kind of science, fascinating and fun :D

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  13. Wow that is brillant. You do a wonderful job, Science was so boring at school for me and now I work in science and I think it is the best thing ever and want to share it with everyone, hooray for experimenting! - Annie

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  14. is is bad to admit I quite like the cola bottles.......

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  15. How fun! (Can I admit that I like jelly sweets?)

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  16. Is that what happened to the senator in X Men?

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  17. I'm going to have to do this with my two over half term! I used to work with someone who used to make vodka jellybabies - might have to try that too....in the interests of science, of course ;o)

    xx

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  18. My kids would so love to try this - what a great class to be a help in - though I'm with you...I wouldn't choose to eat them if offered - before and after.

    Nina x

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  19. blogspot keeps eating my comments... you might get two or none... BUT love your experiments, I still go back to your Harry Potter Xmas present last year. Sigh..

    I can only knit them socks... not as exciting.

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  20. I'm always so impressed by your science with the children - I don't do enough to educate my three at all and leave it all up to school which is silly really. Interestingly though, without any intervention from either parent, Dot is finding herself increasingly drawn to ancient history so having an archaeologist for a dad and a former ancient historian for a mum must have some genetic influence!!

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