Starlets such as Ross Barkley, John Stones and Luke Garbutt have impressed in the pre-season friendlies and England defender Jagielka says the atmosphere under new manager Roberto Martinez is a positive one.
"This is the strongest squad we've had for pre-season for a while," said the 30-year-old on Everton's official website.
"Normally it's been interrupted and we've only had 12, 13 or 14 players, but the manager has got probably 16 to 18 players plus a few of the younger lads on the periphery as well.
"It was fantastic to see Ross come back and enjoy himself and play well. The same goes for John. The manager's got quite a few young lads to look at and that can only make us stronger."
Speaking after a pleasing 3-1 victory over Blackburn Rovers on Saturday, Jagielka added: "It's always nice to be scoring goals and the most important thing is to be creating chances - we did that a lot in both halves.
"We could have created a few more, but we're not going to get carried away - it's only pre-season and a few of the boys have only been back a week or so.
"We're still building up for the start of the season and hopefully when you speak to me in a few more weeks we'll be converting even more chances and looking more solid at the back.
"The manager is excited with the potential he sees and that is the state of play at the moment. We're nothing like a finished project yet, but we put in a really good performance. We're a little bit disappointed to concede the goal, but other than that I thought we pretty much controlled the game.
"We gained valuable minutes and a few of the lads came back a bit later than others so it was nice to see them get their first outing and nice for Jela (Nikica Jelavic) to get a couple of goals."