The Young Lions travel to Monchengladbach on Wednesday afternoon to continue preparing for their first game against Germany on Friday, before then heading to Zagreb to challenge Croatia next week.
"My first impressions are very positive," the former Watford boss told TheFA.com. "Forget about the football for a moment, as young guys wanting to improve and represent their country, they've been brilliant.
England U19s' Euro trip
Germany v England
Friday 4 September 2015
BELKAW Arena, Bergisch Gladbach
Croatia v England
Monday 7 September 2015
Sveti Josip Radnik Stadion, Zagreb
"I've had two sessions with them and I've been very impressed so far. We've still got a bit of work to do to get them blended as a team and become more competitive, but they've created a really good first impression."
The upcoming tests will act as vital practice ahead of the European Championship qualifiers in October.
With World Cup qualification also at stake, depending on how they fare in the Euros, it is a big year for the U19s.
The majority of the group have already tasted success when lifting the Euro title at U17s level in 2014, and their new head coach is aiming high.
"I always set individual targets and ask the players to set their own too so that they can be the best they can be," he added.
"When you are playing for England, that means you want to be the best in Europe and eventually the best in the world, so I think we've got to aim for the stars and see where we get to.
"We'll need a lot of help from our clubs, the development teams below and above us, and we'll also need a little bit of luck as well.
"But we are right at the beginning of a new year so it's a bit of a forming stage. The great thing about this camp is September goes quickly into October and then November - it gives us the chance to work a lot with them.
"So all being well, we will get that talent honed into a team, try and do well and improve on what we have done before."
The campaign could not start any tougher with two testing games this week, but Boothroyd wouldn't have it any other way.
"It's perfect isn't it? Hopefully we'll end the season in Germany at the European Championship, but before we get there we have to make sure we do the qualifying right," he said.
"There's never an easy game, but playing Germany and Croatia gives me a good opportunity to look at everybody before the qualification campaign begins."