Common Core testing is underway in New York state this week, but there was a technical hiccup in a few classrooms. 

The press officer for the 600,000 member strong, New York State United Teachers tweeted its union members reported schools losing tests to blank screens and other issues.

Some schools couldn't log in and for some students multiple choice answers said "system error." 

The New York State Education Department says their vendor, Quesar Assessment, experienced delays and they've been in constant contact with schools.

"We were disappointed, but not surprised that there were some glitches with computer-based testing today," said West Genesee Superintendent Chris Brown in a statement. "In other states that have utilized computer-based tests before New York, there have been glitches.  They were resolved, and I am sure that the glitches that occurred today will be resolved as well. We have a six-day  window to administer these assessments and I see no reason why we will not meet that target."