The Magic School Bus (1994)

S3E7 Makes a Rainbow

The students stumble upon Ms. Frizzle in her closet, engrossed in a pinball machine of her own making that uses light pulses instead of traditional steel balls. As time ticks away and the light pulses dwindle, the kids race against the clock to unravel the mysteries of color, all while trying to keep their activities under wraps from Principal Ruhle!