The ornamental design for a children's camera, as shown and described.
FIG. 1 is a front and top perspective view of a children's camera, showing my new design;
FIG. 2 is a rear and bottom perspective view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a right side elevation view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof; and,
FIG. 9 is an enlarged view of portion 9 shown in FIG. 1.
The broken lines depict portions of the children's camera in which the design is embodied that form no part of the claimed design. The dot-dash broken lines in FIGS. 1 and 9 encircling an enlargement portion of the design forms no part of the claimed design.