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Order the Changes


Can you order these pictures of the development of a frog from frogspawn?
 
 
And these of a bean seed growing into a plant?
 

 
 You can download a copy of the frog pictures here and the bean pictures here.
 
We would be interested to hear not just about your final order, but how you decided upon the order.

Why do this problem?

This problem relates the development of the tadpole into frog, and the growth of a bean seed to changes over time.  Children's idea of time develops slowly. The changes shown in this problem take considerably longer than a day, but much less than a year and so the activity will further learners' knowledge and understanding of the passing of time. Simultaneously, children will be deepening their understanding of life cycles, and gaining valuable practice in looking for similarities and differences, and sequencing.

Possible approach

You will need a set of the tadpole/frog cards from this sheet and the bean cards from this sheet for each pair or small group.  If they are printed onto thin card they will be easier to use and if laminated, they should last a long time.
 
You could start with a discussion with the whole group about how they, and their friends and sisters and brothers, have changed over time. You could invite the class to bring in some pictures of themselves at younger ages or their parents as children to stimulate the discussion.
 
Next you could give each pair/small group all the tadpole and bean pictures mixed up, and ask them to talk about what they see.  If it doesn't come up naturally, suggest they sort them into two sets.  This can then lead into pairs/groups ordering one (or both) set of cards.
 
When they have had time to work on this, the whole group could come together again. Ask them to explain how they sorted the cards. Were there any particular difficulties? How long do they think that these changes would take?

Key questions

Do you think these cards go together? Why?
How will we find a card to go with this one?
Tell me about what you've done.

Possible extension

Learners could find pictures of a similar form of development over time, such as the growth of another kind of plant, for example, a tree, or even mammalian embryology, and sketch out their own set of cards.

Possible support

You might like to encourage some pairs to focus on just one set of cards. Be supportive of any children who would like to look up information to help them order the cards.