Nature Project: What do seeds need to grow?

"How do seeds grow?" 

In response to the children's wondering: "How do seeds grow?" we have conducted a controlled experiment to explore the importance of sunlight and water on seed germination. Today we tallied up the results and wrote some conclusions.

Children planted sunflower seeds in one of 3 conditions:
Group C plants got sunlight and water
Group B plants got no water but they did get sunlight
Group A plants got no sunlight but they did get water.

PREDICT: Which plants do you think will grow the most successfully or not grow at all?
Most students predicted that the plants in group A that were put in the cupboard with no sunlight would not grow. They thought the plants in group B getting no water would also have trouble growing. They thought the plants in Group C would grow the best as they get sunlight and water.

Do you agree????

Here are our results:

Group A Plants (no sunlight) after 2 weeks

RESULTS: 5 out of 6 plants grew, very tall. 

Group B Plants (no water - except for the couple of accidental times they did get water) after 2 weeks

RESULTS: only 3 out of 8 grew at all.

 Group C Plants (receiving water and sunlight) after 2 weeks:

RESULTS: 6 out of 10 plants grew.

We found the results surprising. We did not expect the plants in Group A to grow as well as they did without sunlight. We discussed that clearly water is important to plants as the growth success rate of Group B plants was quite low (only 3/8 grew).

We made sure to compare the growth success as a proportion of the total number of plants in that group (i.e. We cannot compare the 6 growing in group C as better than the 5 growing in Group A because 4 plants didn't grow at all in group C whereas only 1 plant didn't grow from Group A.... perhaps next time we should have the same amount of plants in each group to compare more accurately!)

Today, when writing the results, Gulliver noticed that although the plants in Group A grew tall, they are yellow in colour and the stems are thin and weak, many of them snapping. Whereas the plants in Group C, although shorter, seem greener and stronger (healthier). Great observation Gulliver!

Luis then interjected that he thinks the plants in Group A are tall because they were probably searching for light because they were denied sunlight (in the cupboard). GREAT THINKING LUIS!

Many of the children then said "Yes that's what we saw in the documentary last week about the plants in the forest that climb to reach the sunlight!"

So much learning and discovery is happening and they are using experimenting to confirm facts that they are learning through other sources.