Most of the teachers at first think that this is a cute little experiment, and they decide to amuse me. Then they realize that I am actually going to make them think and participate in the lesson - and things get real. I can almost see the thoughts rushing through their minds... "Wait, don't I just get to sit back and watch because I don't understand Spanish?..." and "You mean she is actually going make me participate - how can she do that? I don't know what's going on!" or "Okay, I understand the word metal because it looks just like the English word - I'm just going to use that word over and over again for everything - I don't care what she's actually asking me."
I give this experience to almost every group that I work with because it is the fastest and most efficient way to get teachers to develop empathy with the English Language Learner students that they see in the classroom, and to understand what their needs are in an academic setting. Inevitably another phenomenon also comes to light. Once the participants understand the fact that I am going to be a mean mean teacher and actually make them participate in the lesson in a language they don't understand, several things happen. Some of them just shut down and refuse to do anything. Some start acting up, acting goofy, and in general become behavior problems. All of them cling to the person in their small group who has the most competency in Spanish. One or two of the small groups decide to ignore my proclamation that I don't understand English anymore, and complete the activity in English anyway, then shove it at me defiantly.
This is always eye-opening for teachers because they are engaging in the same behaviors that they see in their ELL students in the classroom - the same behaviors that have made them absolutely crazy for the last three (or more) months! These are literate and highly educated adults after all. Who would have thought that they would regress so much simply because they couldn't understand my instruction in a second language - with what they all agree would be a very simple activity had it been conducted in English. It is enlightening that these behaviors are not just kids being bad for no reason or to get attention by being the class clown. They are the product of students coping with the fact that they don't understand the academic discourse of the classroom - being overloaded cognitively, trying to save face, trying to distract others from the fact that they really don't know what's going on.
How can teachers help alleviate this?
Use clear and simply stated learning objectives (or learning targets, if you prefer to call them that) - phrase them as "I can" statements if possible.
Give very clear and simple instructions without too many steps to decipher. Give these directions both orally and in writing and leave them up for reference for the length of the activity.
Model-model-model everything you need your students to do - and leave the modeling visible while your students are completing the activity themselves.
Make sure that the vocabulary is accessible to students (on a word wall if necessary).
Allow students to speak to each other in the native language to help increase comprehension as they work their way through complex academic tasks.
Group students strategically, either homogeneously or heterogeneously by language development level depending on the activity.
Learn the language development levels of your students!
Come back to the learning objective at the end of the lesson to have students reflect on whether they reached the objective or not. This should help keep students focused during your lesson because they know that they will have to show that they accomplished the objective at the end of class.
And last, but not least, understand that just because a student can tell you about what they did with their family over the weekend doesn't mean that the student speaks English well enough to keep up with the academic demands of the classroom.