Biology Exploring Life Labs

[April in CA]

Hello Beth and anyone else doing EL labs!

We did the pumpkin lab a couple of weeks ago - my son and two of his buddies are doing labs togather at our house. I thought it went well, and the guys had a good time and learned some things about precision and accuracy in measurements as well as how to estimate sample sizes and manipulate data. wow - that sounds like quite a bit to learn from pumkins, doesn't it?

We used pie pumpkins - each just under a kilogram in mass. We also used Wee Little Pumpkins (official name - I kid you not!) which are a bit bigger than the squatty tiny decorative pumpkins - anywhre from 350 to 550 grams. I bought a large pumpkin just for fun, but we didn't analyze it because I didn't have a way to determine volume.

To find the volume of the pie pumpkins, we used some very high-tech water displacement equipment - a gallon-sized tupperware pitcher and a graduated measuring bowl . Both of these wer set inside a lage rubbermaid tub on my kitchen counter to catch any splash-over. The guys thought that was pretty cool. We did find that we had to press down carefully with one finger to fully displace the water because the pumpkins were somewhat bouyant.

I do have a snazzy digital scale from Home Science Tools that will weigh up to 1000 grams, so we used that to determine mass of the pumpkins and also of all the seeds from each pumpkin as well as the mass of 10 seeds. The guys thought it was pretty neat to use that info to estimate the number of seeds in the pumpkin.

Informally, we discussed sources of error and other things we might be able to do with the data along with why we might care about finding out these things (besiides curiosity).

On Friday, we will be doing the soil analysis lab and the antacid comparison lab. I ordered a couple of soil analysis kits from Home Sci Tools (there is a pattern here...) and I spent at least 15 minutes at Walmart today finding antacids with different active ingredients - I will be stocked if anyone has heartburn!

Home Sci Tools is a great company to order from, and they have lots of things needed for the labs, but they don't have everything. I found pectinase at carolina Bio Supply for $22.00 for 100 ml - now I have to see if I can find it cheaper somewhre else!

I hope you and your son enjoy the labs!
Blessings,
April

[Beth in SW WA]

Thanks, April!
It sounds like so much fun (as much as a bio lab could be :)). I'm placing an order w/ Home Science Tools any day now. Still not sure about the microscope.

Any opinions?

[April in CA]

Hi Beth!

Several years ago, when we began homeschooling, I bought a microscope from Sonlight. I love it! It has all the standard stuff, plus it came with a mechanical stage already attached (ery helpful for adjusting slides.) If it is in your budget, I would recommend getting it, especially if you have younger kids who would benefit from it. I also have a Brock Magiscope, which is a wonderful field microscope - it is virtually idestructible, and you can take it outdoors since it is not electric. I have not had great success with the brock at high magnifications, but at low magnifications it is outstanding - so if you have a but or a stone or something you wnat to get a closer look at, the Brock is great. Your younger children could enjoy it now as much as your older son. I think Jean in Wisconson said she wished that she had had a stereoscope for bio lab work; I would like to have one as well, but the combo of the Sonlight scope and the Brock is pretty impressive, in my opinion. HST has good scopes to - a much wider variety than Sonlight, in fact, but I don't know if any of theirs come with mechanical stages as standard equipment- the mech stage makes scanning so much easier that I would strongly recommend getting one if you can swing it! Happy hunting!
Blessings,
April