Following are the heights in(inches)of 12 student.find the median height. 55,53,54,58,60,61,62,56,57,52,51,63

Arrange the given heights in ascending order:
51, 52, 53, 54, 55, 56, 57, 58, 60, 61, 62, 63

There are 12 data points (an even number). The median is the average of the two middle values. These are the $n/2$-th and $(n/2 + 1)$-th values.
Here, $n=12$, so we need the $12/2 = 6$-th value and the $(12/2 + 1) = 7$-th value.
The 6th value is 56.
The 7th value is 57.

The median is the average of these two middle values:

The median height is 56.5\ inches.