the pdf files must be named as follows:

Explorers_Activity_1_Summary_Teacher_Notes.pdf
Explorers_Activity_1_Worksheets.pdf
Explorers_Activity_1_Detailed_Teacher_Notes.pdf

Explorers_Activity_2_Summary_Teacher_Notes.pdf
Explorers_Activity_2_Worksheets.pdf
Explorers_Activity_2_Detailed_Teacher_Notes.pdf

Explorers_Activity_3_Summary_Teacher_Notes.pdf
Explorers_Activity_3_Worksheets.pdf
Explorers_Activity_3_Detailed_Teacher_Notes.pdf