-For The Arrival, don't play defense. Instead, maximize offense time. Since you don't have to win, switch to man-to-man defense and control the player guarding the ball handler. Simply move away from the player to get him to shoot as soon as possible.
-If you need more time to score points, try fouling players while on defense to get the ball back.
-For The Shootout, after completing the required number of assists, minimize the Hawks offense time by holding on to the ball as long as you can.
-Find all the teams you're going to play against and lower their stats while increasing your own(especially helpful on 'The Shrug'). Since the shoe rewards are random, this just speeds up the process of earning them.
At the Main Menu, scroll down and select "Features", then "Extras, then "Codes". At the codes screen, unlock the following dunks by entering the correspinding codes. Note: After entering the code, load up the Sprite Slam Dunk Showdown and check the Dunk Help menu to view how to perform the new dunks:
At the start of a season you get 10 new drills. Before beginning your new drill, subtract on point from you 3 point stat, which gives you around a 1000 skill points to spend on anything else. Then, complete a shooting drill by attempting only 3s to get your 3 point attribute maxed out again. This is an easy way to get extra skill points. You can do this anytime you get a drill.