Tuesday 21 February 2012

Making our Own Weir

Lately I have been inspired by the blog Science Sparks which is all about doing simple scientific experiments with young kids. As a result, I have been on the look out to add a bit of science into our activities... and the perfect opportunity arose.

The real weir
We were at a park the other day after some heavy rain. This particular park has a series of drainage weirs leading into wetlands. The top weir was draining into a lower pond – causing a waterfall. Cakey was very interested in this and wanted to know why and how. Her questions got me thinking about how I could demonstrate it to her rather than trying to explain.

Setting up our weir
When we got home we got to work making our own weir. I cut out a small section in the side of an ice cream container to mimic the real weir and then placed it into a big tub. We then weighted the ice cream container down with rocks. Cakey added a small amount of water to the bottom of the tub and I mixed in a few drops of blue food colouring. I then added a few drops of yellow food colouring to the ice cream container.

Adding water with a jug
We were all ready! Cakey began to pour water into the ice cream container. As the level reached the cut-out section the water started to cascade over, making a little waterfall. The yellow water from the container mixed with the blue water in the tub and turned green.

This experiment worked really well. Cakey was excited because she was creating her own waterfall and Boo was excited because there was coloured water to play with.

Adding water with the hose
We repeated this experiment over and over, using a variety of different food colouring to watch the mixing effects as the weir overflowed with a cascade of water.

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Linked to The Kids Co-op, Fun Sparks, It's Playtime and Learning Laboratory


  1. Science parks is a great blog!!! I learned something. The mening of weir. Ha! Thanks!!!

  2. What a lovely, visual science experiment! I didn't know the word "weir", either!

    Thanks for linking up to learning laboratory at mama smiles =)

  3. What a neat science experiment! I've found the best ones come from further exploration of everyday experiences--and this one does just that.

  4. Never heard of the word weir before now! Thank you for teaching me some science. I love how this is a science and art experience all rolled into one. I know my daughter would love it!

  5. This is a great way to explore colors and water flow. Congradulations on the award.

  6. What a great water based experiment, Science Sparks has some great ideas :)

  7. I hadn't heard of the word weir either, and I LOVE this idea! Very clever to use the food coloring. I'm sure your kids had a blast. You've inspired me to do some more science. Thanks for linking up with the Kid's Co-op this week!

  8. Thanks for all the lovely comments. Based on a lot of feedback I am guessing that the word 'weir' is not used much in the US. The word 'dam' would also apply.

  9. Great visual demonstration of a weir and loads of fun water play too. Brilliant idea. Ellie

  10. That is a brilliant idea, I know my children would love it!

    Thank you so much for mentioning Science Sparks, I am so glad we inspired you. xxx


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