Hatching Chickens

In our class we have borrowed an incubator from Mrs Wagner's son because over the Christmas holidays last year our school chickens were stolen. We have school chickens, so we can sell the eggs in the office. We use the money for our Enviroschool projects. The money also pays for the chicken feed.
Anyway, in Term 1 we borrowed an incubator but couldn't get any fertilised eggs. We had to wait until spring time to try again. We now have 8 eggs that are being kept warm inside the incubator. But it isn't just a matter of waiting for them to hatch. There are certain things we have to do. Here's what we have found out:
1. Fill the base completely with water. Place the thermometer end into the lid. Place the lid back on and let the incubator reach 37.5 degrees Celsius and 40-50% humidity.
2. Mark the eggs on one side with an X and the other side an O - so when we turn the eggs we will have an X facing the top and then next time we turn them there will be an O on top.
3. Once the incubator is at 37.5 degrees Celsius, place the eggs into the incubator in the centre all facing X upwards then cover with the lid again.
4. Turn the eggs at least 4 times a day for the first 18 days. Each time the eggs are turned, make sure it goes from X to O to X to O etc.
5. Keep filling the small water tray part to keep the humidity at 40-50% for the first 18 days.
6. On about day 10-12, carefully shine a small torch or phone light against the shell. You will be able to see the veins and the new chick forming. If there is nothing, the egg is infertile and no chicken will hatch.
7. Follow all these instructions till day 18 with humidity and turning daily.
8. Day 18 don't turn the eggs, just fill the larger outside water tray and inner so the whole bottom is full with water and bring the humidity to between 70-80%. Cover with the lid again and do not disturb the incubator again.
9. By day 21 our eggs should be pipping and hatching. Try not to disturb the incubator and let the chicks sort themselves. If cracked, but still stuck in the egg shell, we can give them a slight bit of help getting out of the eggs but we have to be careful. Try not to open the lid while the eggs are hatching as this disturbs the humidity and each time the incubator has to build the humidity up again.
10. Once a few or all of the chicks have hatched and fluffed up in the incubator, remove them into a box with a heat lamp, shallow water container and chick crumbles for the first day or two. If any eggs remain unhatched, replace the lid quickly and leave for a couple more days. If they still don't hatch, turn off the incubator and dispose of the eggs.
11. Once chicks are in a brooder box - if they are all huddled together they are cold so the light needs to be lowered. If they are all spread out, the light is too low and needs to be higher. Always have fresh, clean water and keep chick crumbles available all the time. After 3 months, change to a pellet for another 2-3 months then at 6 months when they begin to lay, they can have layer pellets, grains and food scraps.

Things we are having trouble with;

• keeping the temperature at 37.5 degrees Celsius
• keeping the humidity between 40-50%
• turning the eggs 4 times a day when we leave school at 2.30pm.