CALDWELL] NA TURE-STUD Y IN ELEMENTARY SCHOOLS 



365 



Animals — Birds as economic factors; the structure and food 

 habits of common birds; charts showing the relation of common 

 birds to weeds, insects, and to man. 



Physical Materials — Soils — including determination of gross and 

 dry weight of garden soil, amount of gravel, sand, and silt; clay; 

 water holding power of soil; lifting power of soil; soil makers; 

 temperature; erosion by water and wind; conditions for plant 



Fig. 9. Art and Nature-Study. Modelling the Rabbit. 



growth; build cold frames for winter and early spring work with 

 plants. 



Sixth Grade 

 Purposes 

 A more intensive study of problems of living things; garden 

 seeds are collected and number of seeds produced by one plant 

 estimated, this being used for an introduction to the struggle for 

 existence; the pupils may thus learn that more forms begin life 

 than may mature and may see some of the factors which limit 

 them; this study gathers up what has previously been learned 

 about plants and animals and makes a good starting point for 

 personal studies through hygiene; during the latter half of the 

 autumn and the winter quarters hygiene is studied to enable pupils 



