My first science unit inquiry lesson

Tuesday was my first inquiry lesson for our science unit about hermit crabs. The lesson was about asking questions to make an educated guess about what a ceonobita clypeatus is (the scientific name for hermit crab). As I was bringing the students in from reason I began with my lesson attention getter. I had all the students stand up against the wall and I said "Now students when you were at recess something really strange happened. Someone came into our classroom and put something on the wall, we don't who did or why, and we don't know what the word he or she put up means. So I am going to need your help to figure this out." This opener worked like a charm. The students got so engaged at the thought of an 'intruder' type person coming that they pointed out the word I put on the board, and also commented on other things they thought were moved or out of place (even though they weren't). One student even said "I'm going to get to the bottom of this!" Once the students sat down we talked about the word and they had a chance to draw or write what they thought the word meant. One problem, I encountered what that they were riled up by the mystery of some unknown person coming into the classroom that I couldn't get them to stop blurting out or having side conversations. I didn't know how much I could let slide because they were talking about the lesson and they were excited how finding out what the word meant, they were just being a little too chatty and silly. Another issue was that one of hints that the mystery person left was that the creature could live on land or in water. Well the class just finished doing a unit on frogs, and having frogs as class pets so many of them thought the creature was a frog and no one came close to guessing a crab or anything like it because frog was the first thing that popped in their head and so it was hard to steer their thinking and questioning from the frog guess (maybe one of my clues should have been, 'the creature is not a frog'). Teaching students to ask questions can be hard to grasp especially for first and second graders. I actually felt that they understand the concept of educated guesses better than the concept of why scientists asks questions. During my lesson it was hard to stick to my lesson plan because other things kept coming up, so they were some ideas and key phrases I wanted to address but didn't. At times my cooperating teacher say certain ideas I forgot to say and then I would feel a little flustered remembering what I forgot to say, and then I would think in my head that I needed to slow down. Besides that I thought the lesson went well, the students were engaged and seemed excited about it.