Well, I bought the Coursebook, Workbook and Teacher's guide thinking i will have a great tool to prepare my CIE students for the IGCSE exam because they were endorse by Cambridge and they use the same curriculum and syllabus sequence than the exam; the coursebook and the workbook are okay, but i rather use next year the glencoe series since have more tools, labs and exercises. But the Teacher's guide is a RIP OFF!... Is a CD with only 150MB full of PDF's and a mediocre interface with the answers of the problem on the coursebook and workbook. No objectives, goals, teaching tips, exams, quizes, lesson plan help, nothing!!! just A, B, C, D or E answers!... and it cost $44 bucks while the book is only $27!... avoid the CD!... Is going directly to my shelf of forgotten CDs.