My current job at IH Prague gives me a full spectrum of students including pre-school aged groups (4 y/o), lessons at primary schools, as well as lessons in our language school where students are split into 8-10, 11-13, and 14-17 year olds (in addition to being sorted by CEFR language level). I still primarily teach high-level adults, but I have started to really enjoy and look forward to my YL classes.
These lessons vary quite a bit. The pre-schoolers have a three hour "lesson" (only 45 minutes to and hour of which is in any way structured - the rest being a mixture of indoor play time (legos, puzzles, coloring, etc), outdoor playtime (running around, tag, football, etc), and snack time (where I usually get a snack as well!)). The structured parts of the lesson are a mixture of songs, flashcard games, chants and miming games. It's great fun to explore TPR and storytelling with them, and I have really enjoyed trying to bridge the playtime with the lesson. This week and next they're meant to learn "The Itsy Bitsy Spider" during the structured portion of the lesson, and I hope to get them interested in making paper spiders during the indoor playtime to set the tone and playfully introduce some of the language (in addition to the flashcard pre-teaching, of course).
My younger primary school kids are not much different from the pre-schoolers, but they tend to have developed enough socially to work well in team games which involve turn-taking and teamwork. It's great fun to review vocabulary with them with flashcard fly swats and other games like this.
I don't teach any of the 8-10 year old groups, but my 11-13 year olds are a whole different story. They're pre-intermediate (A2) and are old enough that lessons often do resemble adult classes (less of the stir-settle-stir-settle type lesson planning that goes into the younger kids' classes). However their energy and approach to English is completely different and it is great to be able to work on good language learning habits with these kids in the hopes that they will continue into their later years of education. Things like making them aware of the importance of lexical chunks and training them to seek out context clues in the text including the use of relative clauses, pronouns and discourse markers to decide what the function of the unknown language may be. Because of their age and experience in language learning, they seem to be at the stage where developmentally they understand some of the more abstract concepts in English, and enjoy learning how to use it to their advantage - something older learners seem to be more reluctant to integrate into their study methods.
I still treat my teenagers much like I do my adults. This is in part because I still integrate games and less "traditional" techniques with my adult learners, and also because my teen group happens to be quite advanced (C1). However, it is clear to me that they respond different to many tasks due their self-awareness and efforts not to stick out too much from the others in the group. There needs to be more sensitivity to classroom dynamics and relationships between students with teen groups as these can have a major influence on the students' perception of English and their overall efforts in the class.
Teaching YL classes and completing the IH Certificate in Teaching Young Learners and Teenagers course, have been great learning experiences. They have given me some new perspectives on teaching which can apply to all my groups. There is also that constant rumor among EFL teachers that in 10-20 years, most countries will have a much larger YL market than a traditional company/business/adult market due to increasing amounts of students finishing secondary school already at an FCE (B2) level or above. For whatever the reason, I highly recommend teachers give Young Learners a try if they haven't already. If nothing else, you might get a snack!