I think its a good idea, BUT only if the teacher knows how to care for it & willing to take the critter in if it doesn't work out in class.
Back in grade 7-8, the grade 4-5 teacher had a HUGE ginniepig pen in her classroom. She taught the students about animal care, respect & so on. Every year she breed one of the females & would let kids take them home as pets, BUT the kids parents HAD to show up to the parent teacher interview to claim the one their kid wanted & had to listen to care tips & so on about the animal.
In my grade 12A english class, we decided to get a goldfish. I supplied the bowl & airpump. I made sure they only got a little goldfish & said at the end of the year it had to go to a bigger home, like a pond. So as far as I know there was a new fish every year & it went to the bio teachers pond at teh end of the year.
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