Coming from a "Teacher's" perspective, with alterations, I can really see this being used within schools as an extra resource for AEN students, particularly those with Autism/Aspergers.
Fear
This level was definitely one that felt "fearful" as you try to outrun the ghosts. If they catch you, they send you right back to the start. Due to the challenging nature of this level, perhaps you could keep your progress with keys, rather than being sent back to the start with a fresh slate. As this is aimed at children, they can have a short attention span, so as soon as they find a level challenging, it is easy for them to just give up. But if they are shown a sense of progress and achievement, rather than losing all their keys, they can use that as an incentive to keep going and free fear!
Happiness
Doing the three tasks felt nice and purposeful, music was uplifting and really conveyed that sense of happiness. Only nitpick would be the maths section as it felt just a tad out of place with the theme of emotion. Visually, it was engaging, bright and captivating! I can't fault it there.
Envy
Really liked the detail of the blue guys that came over to the platform as every object was placed down. Scenery was very well made and the cut-scenes at the start and end were engaging, conveying the message of "loving yourself". Also, the red herrings placed around was a great touch! Could be nice to see a counter at the top to show the player how many objects they've successfully placed down.
Sadness
The aesthetics of the scenery definitely matched with the theme of sadness. Not too difficult, though going back to the attention span of children I mentioned earlier, the bridges at the end could pop up a little quicker as sometimes I felt they took a little too long to come up out of the water. Nonetheless, this is a lovely level.
Angry
Loved the three challenges of destroying boxes, "whack a wisp", and fighting off the wisps from the well. Metaphorically, the calming down of Anger, going from big to small, was a great touch. It shows the player how anger can manipulate you and turn you into something that you are not. With the help of others, they are able to work together and hone in their anger. However, I will add that the combo of F+space bar was a tiny bit challenging, possibly for those with dyspraxia where they can find button combos difficult to carry out.
Overall, for a children's game it was brilliantly thought out with a clear intention in mind to teach children a better understanding of emotions through a platform which would be more engaging for them in this modern era. The only thing I would point out if I really wanted to be overly nitpicky, would be that emotions could be shown more explicitly rather than taking it out from the scenery alone. Maybe dialogue from each emotion on how being trapped made them feel and even show them expressing that emotion more :)) The opening sequence was lovely for showing each emotion expressed on a face, which is a key resource for those who may have autism.
For a topic and audience, that isn't well represented, I think you all did a fantastic job, especially for your first year of Uni. I absolutely cannot wait to see what you come up with next. I'm very tempted to share this with some teacher friends to see what they think!