The new United manager has had no hesitation in handing 20-year-old Blackett and fellow defender Paddy McNair – who turned 19 in April – their Premier League debuts this season.
Van Gaal has praised the manner in which Manchester-born Blackett and McNair have made the step up and Giggs, one of the Dutchman's assistant coaches and himself a product of the club's youth system, is excited to see the duo flourish.
"That's the philosophy of Manchester United, you always bring young exciting footballers through and the fans demand it and the club demands it," said the former winger.
"Yeah, you spend money on world-class stars, but you also have young players coming through.
"Right from the Busby Babes right from before that, right up until now, you give youth a chance.
"That's what Manchester United have always done and will continue to do."
Under Van Gaal, who succeeded David Moyes, a new-look United have flattered to deceive in 2014-15, producing just one convincing performance in the 4-0 thrashing of QPR last month.
However, United did muster successive wins for the first time under the experienced 63-year-old prior to the international break and next face a daunting run of fixtures that includes games against leaders Chelsea, champions Manchester City and Arsenal between now and the end of November.
Giggs knows the importance of that trio of matches in determining whether United can be considered as title challengers.
He said: "Obviously, we've made a lot of investments this season.
"I think the new boys are starting to settle in and it's exciting.
"We're fourth in the table and we'll look to build from that. We've got a tough few weeks coming up with West Brom [next Monday], and then a real test with Chelsea and City.
"That'll sort of be a test to see where we're at, but we're looking forward to the challenge."
