Houston Zoo is investigating after image of students inside bull pit attempting to pet animal during field trips conducted on campus . Principal of Magnolia High School in Texas issued apology to zoo for students ' behavior ; also said field trips to zoo will be canceled .
Houston Zoo is investigating after image of student inside jaguar pit attempting to pet animal during field trip surfaced on Twitter . Principal of Magnolia High School in Texas issued apology to zoo for students ' behavior ; also said field trips to zoo will be terminated .