Final answer:
The symptoms described by the student suggest that the child may have Attention Deficit Hyperactivity Disorder (ADHD), which is characterized by inattention, hyperactivity, and impulsivity.
Step-by-step explanation:
The characteristics described of a first grade child with messy handwriting, difficulty knowing the alphabet, being easily distracted, unable to sit still for more than a few minutes, and described as very fidgety are indicative of Attention Deficit Hyperactivity Disorder (ADHD). ADHD is a neurodevelopmental disorder where affected individuals have a hard time maintaining attention and controlling impulses. Symptoms include inattention, executive functioning difficulties, impulsivity, and hyperactivity that exceed normal developmental stages. While other conditions like dyslexia and autism spectrum disorder (ASD) have their own distinct characteristics, the behaviors described align most closely with ADHD, amongst the given options.