800 BIRD FRIENDS 



D. Problems on migration. 



1. Some Arctic terns travel each year from the edge of the 

 Antarctic continent to the most northern part of North Amer- 

 ica, a distance of 11,000 miles. It takes the bird about 20 weeks 

 to make the round trip. How far does it travel in a day? 



2. The robin as a species travels from Iowa to Alaska, a dis- 

 tance of 3000 miles, in 78 days. How many miles does the robin 

 average to travel in a day? 



E. Problems on the number of birds killed by cats. 



1. A man in Massachusetts wrote to many people in the 

 State asking about the number of birds killed by a single cat. 

 The answers received from several hundred persons showed that 

 on an average a cat kills 33 birds during 1 month at the height 

 of the nesting-season, and that each farm averages to keep 2 

 cats. There are in the State 37,000 farms. How many birds do 

 the cats on these farms kill each season? 



2. Find the number of cats kept in your locality, and estimate 

 the number of birds killed each year by these cats, assuming, as 

 in the previous problem, that each cat kills 33 birds in a season. 



F. Miscellaneous problem. 



1. A study of hawks made by the United States Department 

 of Agriculture showed that 5 kinds were harmful, 7 kinds were 

 neutral, and 35 kinds were beneficial. What per cent of the 

 hawks respectively are harmful, neutral, and beneficial? 



Essentials of a good lesson. As previously men- 

 tioned, the teacher needs to consider the matter of 

 materials in planning for a bird lesson; and it is 

 also suggested that a consideration of the three 

 following points for each lesson or topic taught may 

 prove helpful: (1) the child's problem; (2) the de- 

 velopment of the lesson based on the problem; and 

 (3) the application or use by the child of what he 

 has been taught. 



Child's problem. The child's problem is a means 

 of arousing the child's interest. It should be a ques- 



