yes it is possible for a child to be in CTD classes and not gifted. CTD requires 95th percentile on NWEA MAP. That could be a high achieving child and not a gifted child. They do not require IQ testing but accept it for entrance.
(CTD is Northwestern University Center for Talent Development)
Here is their eligibility requirements
Eligibility
CTD Academic Evaluation | Acceptable Tests for SEP Eligibility | Admission Portfolio
To qualify for Saturday Enrichment Program (SEP) admission, students must be age 4 through grade 9 and must also provide evidence of one of the following criteria:
Successful completion of a Center for Talent Development Saturday Enrichment Program, Gifted LearningLinks or Summer Program course in the subject area of the SEP course to which student is applying;
A score at the 95th percentile or above on a nationally normed standardized test in the subject area of the SEP course to which student is applying;
Participation in above grade-level testing such as the EXPLORE test taken in grades 3, 4, 5, or 6, the ACT or SAT test taken in grades 6, 7, 8 or 9 (Talent Search).
Qualifying academic evaluation (available to students age 4 through grade 3) performed by Center for Talent Development or a similar testing agency; or
Submission of an Admission Portfolio (an option only for students in grades 3 through 9).
