The Progressive Peak English Course Supplementary Readers There are twelve readers in this series. The stories are fun to read. Lost Parcels Chao and Wakio find a lost bag and return it. They lose a parcel.
The books in this series 
SR1 Kadogo at School 
SR2 Emma, Jim, and the Goat 
SR3 Our Market 
SR4 A Reel of Cotton 
SR5 Blue Flowers 
SR6 The lazy little Zebras 
SR7 Wasike and the Birds 
SR8 Lost Parcels 
SR9 The Old Cat 
SR10 Kantai and the Cows 
SR11 A Present for Aunt 
SR12 In the Countryside