Rinse your grapes under cool water and pat them dry with a towel. If you like, pull a few off the vine for easier snacking, or leave them attached for a fun presentation. Set them aside while you prep the rest.
Cut your apple into thin wedges or slices, discarding the core as you go. Toss the slices with a small squeeze of lemon juice to stop them from turning brown before lunchtime arrives.
Slice your cheese block into small, bite-sized cubes using your paring knife. Keep the pieces roughly the same size so they're easy for little hands to grab and eat.
Place the grapes in the largest compartment of your lunchbox, then add the apple slices right beside them. Put the cubed cheese into its own separate compartment so it doesn't get squished.
Tuck the almonds into the smallest compartment, or swap them for a hard-boiled egg if you want more staying power. Close the lid, pack it into an insulated lunch bag with an ice pack, and it's ready to go.