How do you get past the two boys in the paved courtyard in Harry Potter and the Half-Blood Prince on Nintendo ds?

In "Harry Potter and the Half-Blood Prince" for Nintendo DS, to get past the two boys in the paved courtyard, you need to use the Disarming Charm (Expelliarmus) to distract them. Approach them stealthily and cast the spell, which will cause them to drop their items and move away briefly. This gives you the opportunity to slip past them and continue on with your quest.