Monday we made "baking soda bombs". Looking back, I realize I maybe should have called it something different. Haha. It got the kids more amped about it, though, so I guess it works. Basically all you do is put water, vinegar, and baking soda in a Zip-loc bag, seal it and wait until it explodes. To make it a true experiment and not a demonstration, we had to choose a variable to change. I figured the easiest was water temperature, so we did that.
Note to self: try experiments first alone before attempting them with students.
As soon as we poured everything into the bag, my students started running away and hiding behind boxes to avoid the explosion (See pictures below: I'm not exaggerating! Haha). One student put a pencil near the bag to 'see the force of the explosion'. But, let's just say the "bombs" were more like the watched pot that never boiled. :)When it did eventually "explode" it was a muffled 'pop' that only half my students heard. Since I didn't have enough baking soda to do a second trial with increased proportions, we scrapped the original experiment and decided to see if the amount of baking soda made a difference in the speed of the pop. It was actually quite useful in teaching students about a fair trial (only one variable, everything else constant) and a botched experiment.
On Wednesday we did the homemade helicopter experiment. Does the length of the propeller make the helicopter fall faster or slower? We got differing results, so we must've not done something right... Maybe because we made them out of paper instead of cardstock? Maybe our drop height wasn't high enough? Maybe our timing was semi-inaccurate since some of them didn't actually drop their helicopters till like 3 seconds after I said "Drop"? :)
Finally, on Friday we did my all time favorite Science experiment: The Soda Fountains! Let's just say... Malaysia 1, Ms. Wacek 0. First of all, I didn't have Danielle with me as my 'professional Mentos dropper-inner". Secondly, I didn't have the handy Mentos dropper-inner tool Nate got for us last year. Thirdly, Malaysian soda is apparently not the same as American soda. While they still got the picture and enjoyed it, the experiment was wayyy less exciting than the 12 foot fountains we've made in years past!
|I definitely need practice at getting all the Mentos in more quickly.. Both for the experiments sake and so I don't end up covered in soda!|