Afterschool Grade 3 & 4 workbook recommendations?

[C3PO]

Hi folks,

     I'll be teaching a morning class (afterschool-style) for mixed level students 3rd-4th grade.  My principal wants to be on par with hagwons so he wants a class with "sparkle" and not "same same" structure of a usual class.
 
    I have fortunately been given the opportunity to search for some kind of text or workbook for this class and was wondering if you had any suggestions...A book that has different activities, is easy to follow, and uses authentic English-- focus will still be on speaking.

   What luck have you had with workbooks?!  Thanks in advance!!

[daninsanam]

I would recommend the Sounds in Action books by Julie Sormark... they are easy to use, focus on speaking and a readily available in Korea. I have used them for afterschool 3 & 4 a bunch and the kids like them. The songs are much better written than most of the textbooks you'll find.