Allen Park — After Wednesday’s walkthrough and some meetings, Lions training camp for 2015 will officially close.

And after weeks of practice with a dozen sessions, coach Jim Caldwell praised his team’s work.

“I thought overall we had a very, very good camp,” he said. “I thought we learned and developed; I thought we grew.”

The Lions have their second exhibition game Thursday in Washington, and upon returning to Detroit, the team will begin preparing with more focus specifically on the regular season. The practices will once again be closed to the public and, apart from a brief portion of individual drills, the media.

“It’s sad to kind of see the fans go because of the fact that they add a lot to practice,” Caldwell said. “I think most people understand that we have guys that aren’t too bashful about playing in front of people, but nevertheless, our practice probably was kind of middle of the road.”

Caldwell said the team had too many miscues Tuesday, but overall, he thought the two-plus weeks of camp went well, noting the team’s mostly strong performance in last Thursday’s exhibition win over the New York Jets.

Part of the success came from many of the 90 players understanding the gravity of their situations as they compete to make the 53-man roster.

“They understand the importance of doing well and functioning well, and I think they concentrate and they focus on doing just that,” Caldwell said. “Younger guys understand it, the older guys certainly understand it, particularly some that have been around a while and are competing for a spot.

“There’s only so many of these jobs that go around, and these jobs are pretty good gigs.”

After some errors in practice Tuesday, Caldwell said he’s hoping the team can fix its mistakes in advance of Thursday’s game at FedEx Field.

And even though the training camp performance was encouraging, Caldwell isn’t resting easy with regards to what lies ahead. His response to a question about the team’s confidence in the kicking game — with Matt Prater replacing last year’s training camp dud Nate Freese — perfectly summarized his thoughts moving forward.

“My mind’s never at peace, not in coaching,” he said. “You don’t have any of those days.”