Easy "Suddenly, Noodles" achievement
Open the crate in the right rear corner of Mike's room in level 1.
Easy "Time Travel" achievement
The secrets are found in the following locations.
On the desk in rear right corner of the hangar.
Near the power line at the top of the comms tower.
Inside the first empty spacesuit pod on the left when you first enter the control room.
Easy "Wake Up and Play!" achievement
The secrets are found in the following locations.
Go to the crate at the rear right corner in Mike's room.
Use the screwdriver to open the vent in your bedroom.
Search behind the monitor in the rear center of the storage room.