There’s one piece of advice I keep hearing over and over again when it comes to implementing NGSS successfully: Do less talking about and make kids do more figuring out. I’ve accepted this mantra as a personal challenge. This school year I’m analyzing all of my curriculum and trying to tweak it to make it more NGSS friendly. Every activity needs to be more inquiry-based. Every lab needs to be hands-on and less “cook-book.” Kids need to be communicating more with their peers through conversation and written word. This week my students tackled naming compounds and they gained formula writing skill through inquiry-based lessons.
NAMING COVALENT COMPOUNDS
Teaching ionic formula writing requires some degree of direct instruction. But lately I’ve found that kids can figure out how to name covalent compounds and acids without my help. In both regular and accelerated classes, I started my chemistry students off with a list of 10 covalent compound formulas and the corresponding names. With teacher guidance, the class determined that covalent formulas look different than the ionic formulas that we previously mastered. Covalent formulas appeared to contain all nonmetals (and some metalloids) whereas ionic formulas typically contained metals and nonmetals. At this point students assembled in teams of three at the lab counters and I encouraged them to look for similarities in the names. “Do the covalent compound names have anything in common? Do you see patterns emerging?” I pushed them to write down five rules that they could use to successfully name any covalent compound.
My accelerated students accepted this challenge more readily than my regular level students. However, with small pushes and carefully directed questions, my regular level students excelled in this inquiry activity equally as well. I worked the classroom during this activity, going from group to group, prompting teams to give me feedback on what they had learned so far. I also left each group with a question or a statement. In some cases I highlighted a
prefix like “mono” and asked them to tell me something unusual about how it was used. If a team told me that “-ide” was used as an ending, I inquired whether it was used on both elements or only one of the elements. Students struggled to put their ideas into words. NGSS Science and Engineering Practice 8, Obtaining, Evaluating, and Communicating Information, requires students to communicate scientific ideas orally and textually. This activity offered a great opportunity for students to put scientific rules into their own words. Kids often told me, “I know what it means but I can’t put it into words.” I encouraged kids to keep the words simple and make sure they understood what they put down on the paper. When I sensed the teams were slowing down or finished, I stopped class and called on one group at a time to give me a covalent naming rule that they believed everyone should have written down. At this point students fine-tuned their rules if they felt another group provided a better explanation.
Covalent Naming With Inquiry
Given that my students learned covalent naming rules with great success, I got gutsy and tried a similar tactic with naming acids in my accelerated classes. Since this lesson required more attention to detail, I created a handout that led students through a series of inquiry based questions. Students completed the worksheet for homework by themselves. Upon returning to class, students were placed in teams of 2-3. To incorporate SEP Practice 7, Engaging in Argument from Evidence, I told students they needed to convince their partner that their acid naming rules were correct. Together the teammates compared and evaluated their opinions. Upon completion of the activity, they established a consensus on the correct acid naming rules.
Different groups were called upon to share their rules. Not only did they correctly determine the various acid naming rules, their ingenuity in creating memory devices for oxyacids surprised me. Students determined that when naming acids involving anions ending in “-ate” they needed to change the ending to “-ic acid.” Students invented memory devices like “I ATE something and it was ICky” or “I ATE something and it made me sICk.” I loved their memory devices for oxyacids involving anions ending in “-ite.” To remember the change from “-ite” to “-ous acid,” they created devices like “They did not invITE US.” A more positive spin on this one was “Chemistry will unITE US.” Loved it!!
Naming Acids With Inquiry
As I adapt my curriculum I always reflect on the lesson and ask myself “Would I do it this way again?” For both covalent naming and acid naming, the answer would be a resounding yes. Using inquiry encouraged students to think for themselves, engage in argument with classmates, and write scientifically. Both activities promoted science and engineering skills highlighted by NGSS.