My colleague, Miss Nasitir found a wonderful website that your students can practice their balancing equations on an actual balance.
Hooda Math ( http://www.hoodamath.com/ ) is a wonderful website for math games. I used this with my 3rd graders last year and they loved it!
I am planning some more project based learning for May and am super excited to get your kids up and moving!!
As always, please feel to contact me!