Cook the acini di pepe pasta according to package instructions; drain and rinse with cold water.
In a large bowl, combine the cooked pasta and sugar, mixing well.
Add the drained crushed pineapple and stir to combine.
Gently fold in the mandarin oranges and shredded coconut.
In another bowl, mix the milk and lemon juice, then add to the pasta mixture.
Stir in the mini marshmallows and whipped topping until evenly distributed.
Cover the salad and refrigerate for at least 2 hours.
Before serving, give the salad a gentle stir and adjust sweetness if necessary.
Garnish with fresh mint leaves on top.
Serve chilled and enjoy!