'Nightline' Daily Line, Dec. 18: Threat Closes Other Newtown School

7:19 p.m. ET: Do violent video games train teens to kill?

Credit: Digital Vision/Getty Images

Dr. Chris Ferguson has conducted a series of multi-year studies of young people, 11 to 18 years old, to find out if violent video games affect their psyches. His conclusion: There is no evidence that exposure to violent video games leads to violent behavior.

What do you think? Read the full story HERE

5:23 p.m. ET: The National Rifle Association has broken its silence on the mass school shooting in Newtown, Conn., saying it is ready to "offer meaningful contributions" to the effort to make sure there are no more incidents like the one in which 20-year-old Adam Lanza used an assault rifle to kill 27 people before killing himself.

Read the NRA's full statement HERE

4:02 p.m. ET: UPDATE: Instagram tweets:

2:10 p.m. ET: Instagram, the popular service for sharing and filtering photos shot on phones, has now released changes to its Terms of Use, which will go into effect on Jan. 16, 2013 for all users. "Our community has grown a lot since we wrote our original terms of service. To get things up to date for the millions of people now using Instagram, we're bringing you new versions of our Privacy Policy and Terms of Service," Instagram wrote on its blog.

In a nutshell: Instagram is claiming the right to license users' photos to advertisers without compensating users or even getting their consent.

Read the full story HERE

Credit: ABC

12:55 p.m. ET: NEWTOWN UPDATE: Local officials closed a Newtown, Conn., elementary school following a threat on what would have been the first day of classes since a shooting rampage at nearby Sandy Hook Elementary School.

Classes at Head O'Meadow Elementary School were scheduled to begin at 11 a.m. ET, but as parents and students arrived at the school they encountered police who turned them away.

Read the latest HERE

Credit: AP Photo

11:55 a.m. ET: Now for something a little different - a sign of the times?

A 4-year-old boy's big sister who went to bat for him by petitioning Hasbro to make a version of the classic Easy Bake Oven for boys got a surprise this holiday season when the company invited her to see the new, boy-friendly model of the timeless toy.

McKenna Pope, 13, didn't have to go all the way to the North Pole, but simply went to YouTube to make an appeal for her 4-year-old brother, Gavin, and the one thing he wants from Santa this year.

"I want a dinosaur Easy Bake Oven," Gavin said.

Read the full story HERE

Credit: ABC

10:01 a.m. ET: A president at a crossroads. In the wake of the Sandy Hook Elementary School shooting massacre, ABC's Jake Tapper takes a look at what President Obama's next moves are on gun control - and if Washington will act.